: 2006 STS V6 Surging Issues



kschwed
08-24-12, 11:01 PM
I'm experiencing some surging at around 25-30MPH (with light acceleration) and 65-80MPH (with moderate acceleration). It is easy to reproduce.

Any idea what could be causing this?

Mullah88
08-24-12, 11:08 PM
mine was the ignition coil and a spark plug in cylinder number 2. also happens in heavy acceleration around 40mph and 80mph for me

kschwed
08-24-12, 11:13 PM
Im at about 67K miles. Doesn't that mileage seem premature for an ignition coil? What did the fix cost?

Mullah88
08-24-12, 11:26 PM
am at 144k lol...it was under warranty (3rd party...warrantydirect), just paid the $100 deductible

kschwed
08-24-12, 11:30 PM
Yeah, but at 144k, you can expect to see some issues like this. Do you remember what you were quoted though?

truckinman
08-25-12, 10:07 AM
Most likely it's an ignition coil. I've got 88k on my 05 3.6 and mine started doing the same thing. Had it scanned at autozone, and found that cylinder 3 was misfiring. Btw, my check engine light had flashed at me a couple times which is why they found something with the scanner.

Since any number of things can cause a misfire, I went home and simply took the #3 coil out and swapped it with #5 coil. Figured if it's the coil 5 should misfire now. Drove it around until the CEL flashed at me again, took it straight back to the zone, they scanned it and found I was right. Now #5 was missing. So that made it obvious that it was the coil.

It's always best to start with the simple things first tho. Could be as simple as a very dirty throttle body. I bought a can of TB cleaner, first, for 5 bucks and cleaned it out just for the heck of it. Then used some techron fuel injector cleaner for 10 bucks. And worked my way to the coil.

truckinman
08-25-12, 10:11 AM
I picked up the ignition coil for just under 70 bucks. It's a relatively easy job. Is your car the 3.6 or 4.6? Bc I've been reading that it really does seem to be a common problem at around 80k miles. Does your car throw a check engine light? Flashing or steady?


EDIT: just realized u have your engine in title. Lol. So yea it's an easy job if you plan on doing it yourself. If you take it to a garage tho Depending on the location of the coil/spark plug, it could be 250 bucks or so. #5 hardly takes anytime at all to get to. Once you get that plastic cover off, it's in plain view.

kschwed
08-25-12, 04:45 PM
Thank you for you help, everyone. It's never thrown a CEL, so I will probably wait until it does and scan it. I'll likely do the work myself. $70.00 and dirty hands beats $250.00. Do you have a guide on how to replace the coil?

truckinman
08-25-12, 09:13 PM
Thank you for you help, everyone. It's never thrown a CEL, so I will probably wait until it does and scan it. I'll likely do the work myself. $70.00 and dirty hands beats $250.00. Do you have a guide on how to replace the coil?

I did put the new coil in and she runs like a brand new car. Got all it's power back.

I don't have a guide but can kinda walk you thru it. There's a guide somewhere on here if you search "ignition coil replacement" or something like that. It's on an SRX but with our engine. Same exact set up. Once you take off the cover, there's 6 13 mil bolts to take outa the upper intake manifold so you can move it from side to side to make room for cylinders 2, 4, 3, and 1. The evens are on the drivers side and odd on passenger.

Another bolt to take out to free up the intake is the front anchor pin for the plastic cover. That's a 10 mill bolt. Then the bolts for the coils are also 10. Just need enough extensions to get to them.

It's really an easy job. Hope this helps ya if you find out you've gotta misfire.

kschwed
10-09-12, 01:41 AM
So this problem seems to have gotten worse. Tonight, it would stutter every time I would accelerate. The CEL started flashing at me and eventually it just stayed solid. I'm thinking about taking this to Autozone to get scanned. Any advice?

truckinman
10-09-12, 07:27 AM
So this problem seems to have gotten worse. Tonight, it would stutter every time I would accelerate. The CEL started flashing at me and eventually it just stayed solid. I'm thinking about taking this to Autozone to get scanned. Any advice?

Yep. Take it to any auto parts store and have em scan it for free. I'm 98% sure you'll find one or more of your cylinders mis-firing. And most likely it'll be an ignition coil.

kschwed
10-09-12, 10:12 AM
Thanks for the info. The scanner will tell me which coil it is, right? That's a part I can acquire from the dealership, correct? I haven't done maintenance like this before. If I have to drive it, is it safe?

truckinman
10-09-12, 11:14 AM
Thanks for the info. The scanner will tell me which coil it is, right? That's a part I can acquire from the dealership, correct? I haven't done maintenance like this before. If I have to drive it, is it safe?

Some scanners will just bring up a code that it finds. I can't remember exactly what the code is for misfire. But its something like "M01". Well the "01" or 2,3,4,5, or 6 in the code is the cylinder that's missing. But autozone usually has one of the nicer ones that actually will say "cylinder 3" etc... But it won't tell you plain as day that its a coil. It'll just say misfire which can be any number of things having to do with that cylinder. From a coil to a spark plug or injector. That's where the process of elimination comes into play. And if it's only saying one cylinder is missing, swap the coil of said missing cyl, with a cyl that isnt missing. Drive it around until the CEL comes back on, and scan it again. If that cylinder you put the supposed bad coil on is now missing but the original cylinder isnt anymore, you know it's the coil. If the original is still missing, you know you've gotta keep looking.

Yes you can buy this part from dealer. However, I bought mine for 70 bucks from autozone with a 2 year warranty I believe. Which 70 is less than dealer would sell the part for. Granted it would be a factory part, but as far as I'm concerned, not really worth the price difference if you are doing it yourself.

And no it's not a good idea to drive on a missing cyl for very long. If it's just a week or so, most likely no long term effects. But for an extended period, it can lead to far more pricey fixes. So the sooner the better

----------

Oh and FYI, if you do swap coils, make sure to swap with a cylinder that's easy to get to. That way you don't have to remove the intake again. On mine, 3 was missing. So I put it on 5 bc you can get to cyl 5 by simply taking off the plastic cover. No removal of intake. Bc 3 was a bit tougher to get to. And in case your wondering, the cylinder #s are as follows.

5,3,1 on passenger side

6,4,2 on drivers. That's from firewall to front

dkozloski
10-09-12, 12:11 PM
Be aware that when you drive around with a misfiring engine like with a bad coil, you're ripping the Cat convertor for that cylinder bank. Penny wise and pound foolish.

kschwed
10-09-12, 02:22 PM
Be aware that when you drive around with a misfiring engine like with a bad coil, you're ripping the Cat convertor for that cylinder bank. Penny wise and pound foolish.

Yeah I totally understand that. I was more concerned with the fact that I drove home about 10 miles last night like that and that I'll need to drive a few more tonight to get the parts I need. ~15 miles shouldn't cause much damage, right?

truckinman
10-09-12, 03:09 PM
Yeah I totally understand that. I was more concerned with the fact that I drove home about 10 miles last night like that and that I'll need to drive a few more tonight to get the parts I need. ~15 miles shouldn't cause much damage, right?

You'll be fine

kschwed
10-09-12, 05:53 PM
You'll be fine

Good to know, thanks. Would you be able to offer any guidance as to how to properly replace/install the spark plugs? Any specific tools needed, etc? Also, how long did it take you to do this job, minus driving around and switching the spark plug from cylinder 3 to 5?

Thanks.

truckinman
10-10-12, 12:59 AM
Good to know, thanks. Would you be able to offer any guidance as to how to properly replace/install the spark plugs? Any specific tools needed, etc? Also, how long did it take you to do this job, minus driving around and switching the spark plug from cylinder 3 to 5?

Thanks.

Well you won't need to touch the spark plug until you've ruled out the ignition coil. But if you do need to remove the plug itself, all you need is a 5/8 spark plug socket. I believe it's 5/8 anyway.

To get to the number 3 cyl, it took me maybe 15 min. And everything else was hardly time consuming at all. As I said, I put bad coil in cyl 5 bc cyl 5 is so easy to get to if I found that coil to be bad. Which I did. And it then took 3 min to get back to cyl 5 to get the coil. All you gotta do to remove coil once your there is unbolt two bolts from the coil...10 mil I THINK....then unplug the wiring harness then pull straight up. May have to put a little effort into pulling it off the spark plug. But then the coil boot and everything will come out and that's that.

kschwed
10-10-12, 01:26 AM
Well, it took me a bit longer than 15 mins. I took the intake manifold off the top of the engine (which was kind of a pain in the butt) and moved it aside. My scanner told me it was coil 3. I popped it out and replaced it with a Duralast Gold one from Autozone. Cleared the code. Drove around for 10 minutes. Floored it a few times. No more CEL. It drives a little differently too. Definitely can tell that it has more power.

Thanks for all your help everyone, especially Truckinman.

truckinman
10-10-12, 02:23 AM
My pleasure! Glad I could help! I'm glad it's working for you again. Yea, when I replaced mine, it was like driving a new car again with all the power I got back. It's always good to find out, too, just how easy it is to work on the basics of this engine. I only really ever worked on my jeeps b4 this car. Besides the time I changed the struts in my Lexus. That was a pain. Had to remove back seat. But, point is, my jeeps were always so easy to work on with their straight six. So when I had to work on my caddy, it intimidated me a bit just bc it's much fancier. Lol. But now I realize, basically an engine is an engine for the most part. I love working on cars almost as much as driving them. Lol

But anyways, didn't mean to turn this post into an auto-biography. Lol. Glad you got her running smooth again!

kschwed
10-14-12, 12:30 PM
So this problem may not be squared away yet... Last night, when I was driving up a hill, my car stuttered a bit, but it was a smoother, less jerky stutter. No CEL came on or anything. Could it be that another ignition coil is on its way out?

EChas3
10-14-12, 04:21 PM
A bad coil should set a misfire code.

The fuel filter is cheap to replace but it does require a special tool.

dannyquest
10-14-12, 11:36 PM
kschwed, My 06 STS did the same thing. No codes, got worst over time. Changed spark plug, didn't help. The car chuggle while going up a slight up hill under light throttle. Bad torque converter. Cadillac know about this problem. First they want you to pay ( $ 130.) for a computer program that won't work. Just take it to your local transmission shop that is trusted. Danny

kschwed
10-15-12, 01:00 AM
kschwed, My 06 STS did the same thing. No codes, got worst over time. Changed spark plug, didn't help. The car chuggle while going up a slight up hill under light throttle. Bad torque converter. Cadillac know about this problem. First they want you to pay ( $ 130.) for a computer program that won't work. Just take it to your local transmission shop that is trusted. Danny

I hope that isn't the case. There are two things that lead me to believe that this may not be correct for me.

1 - I did get a misfire code, and changing an ignition coil seemed to help the problem a lot.
2 - I had a new torque converter put in (under warranty) 30k miles ago. I'm only at 70k miles

kschwed
10-15-12, 05:27 PM
I was thinking that maybe my check engine light / cylinder 3 misfire were completely unrelated and coincidental to the original reason for posting this thread.

You'd think a new torque converter would last more than 30k miles. If Cadillac knows about this problem and they put a new one in less than 3 years ago, what are the chances they would warranty their work?

EChas3
10-15-12, 08:38 PM
The 'Chuggle' is a V8/AWD issue. Your bad torque-converter may have been a symptom of something mis-alligned, etc. Maybe you should consider a used/rebuilt transmission.

As you note, the first TC should have gone far beyond 30k.

Good luck!

kschwed
10-16-12, 01:19 AM
The 'Chuggle' is a V8/AWD issue. Your bad torque-converter may have been a symptom of something mis-alligned, etc. Maybe you should consider a used/rebuilt transmission.

As you note, the first TC should have gone far beyond 30k.

Good luck!

I'm not sure I completely understand your suggestion. This is a V6. Are you implying that my torque converter went bad due to a faulty transmission?

On a separate note, shouldn't the dealership be on the line to fix this, seeing as though it's a powertrain part that they serviced less than 3 years ago?

EChas3
10-16-12, 07:21 PM
I'm not so sure your issue is the one described by the 'Chuggle' TSB. Other things can wear out a torque converter. I wish you luck in getting it covered unless you have an active extended warranty. If it isn't covered, I'd strongly consider replacing the complete tranmission with a rebuilt one or trading the car.

Opinions vary.

kschwed
10-18-12, 01:26 AM
I'm not so sure your issue is the one described by the 'Chuggle' TSB. Other things can wear out a torque converter. I wish you luck in getting it covered unless you have an active extended warranty. If it isn't covered, I'd strongly consider replacing the complete tranmission with a rebuilt one or trading the car.

Opinions vary.

Why do you suggest completely replacing the transmission or replacing the car? I don't understand why you're suggesting that this may be so monumental that I may need to trade in my car. I know a new torque converter is not cheap, but why would I need a completely rebuilt transmission?

truckinman
10-18-12, 05:43 AM
Why do you suggest completely replacing the transmission or replacing the car? I don't understand why you're suggesting that this may be so monumental that I may need to trade in my car. I know a new torque converter is not cheap, but why would I need a completely rebuilt transmission?

I think what he's saying is, and feel free to correct if wrong chase, there could be something in the tranny that's bad, causing the TC to go bad so quickly and if that's the case, it may be easier to just have it or the car replaced.

kschwed
10-18-12, 03:49 PM
I think what he's saying is, and feel free to correct if wrong chase, there could be something in the tranny that's bad, causing the TC to go bad so quickly and if that's the case, it may be easier to just have it or the car replaced.

Understood. Can anyone shine any light on what it is that could be causing this? I have a feeling that my dealership might be willing to work with me on this if I go in there with an idea of what this is. They're more willing that most.

Thanks.

EChas3
10-18-12, 08:34 PM
^^^ That's it exactly.

Sorry to be negative, it's not really my nature. I started hanging out around here about 4 years ago and had a stretch with a lot of time to kill and may have read every STS thread.

I certainly don't claim to remember them all, but 2 torque converters in 60,000 miles is more than rare; it's nearly unprecedented. If the first one was done right, something else in the tranmission is causing it. I do not believe in lemons; it's a machine. Machines with personality need repair or replacement.

kschwed
10-19-12, 12:39 AM
^^^ That's it exactly.

Sorry to be negative, it's not really my nature. I started hanging out around here about 4 years ago and had a stretch with a lot of time to kill and may have read every STS thread.

I certainly don't claim to remember them all, but 2 torque converters in 60,000 miles is more than rare; it's nearly unprecedented. If the first one was done right, something else in the tranmission is causing it. I do not believe in lemons; it's a machine. Machines with personality need repair or replacement.

And I totally agree with you, which leads me to another alternative explanation. Perhaps it isn't the torque converter and never was, because to be completely honest, I don't really think the problem ever went away when they "fixed" it the first time. This isn't something that always happens anyway. Sometimes it will happen for a week at a time and be relatively easy to reproduce. Other times I cannot cause it to happen. But it is most likely to happen during moderate acceleration going up hill. I would think that such a mechanical part as a transmission would either work, or not, but not work for weeks at a time. It's never so dramatic that I think it's about to break or stall and it ONLY happens between 25-30MPH and 65-75MPH. It really is a bizarre problem.

kschwed
10-19-12, 06:12 PM
I spoke with my trusted (and I really do trust this guy) service rep at the dealership about this today. He though the problem was about as bizarre as I do and he also told me that his own car (not a cadillac) does this same thing. He didn't suggest that it was even related to the transmission. He thought a fuel filter could be a cause, but he recommended that I let one of his techs drive it. He also said that this doesn't sound remotely like a torque converter issue.

I'm more confused now.

truckinman
10-19-12, 07:29 PM
Well, fuel filter is cheap enough. May as well try that. Prob wouldn't hurt to replace anyway as a preventative maintenance thing

Mullah88
10-19-12, 09:43 PM
mine has been fixed (ignition coil, and spark plug change) but the damn light is still on and i have a check gas cap message on the DIC??

EChas3
10-19-12, 10:46 PM
Some cars develop condensation/corrosion on the cap or filler.

If so, clean, dry and apply a thin film of petrolium jelly. Does the cap seal better? Buy a new one if needed.

kschwed
10-19-12, 11:21 PM
mine has been fixed (ignition coil, and spark plug change) but the damn light is still on and i have a check gas cap message on the DIC??

What symptom were you experiencing? Did the check engine light come on for a misfire, or are we talking about the chuggle you get when accelerating?

Mullah88
10-20-12, 04:20 PM
the car chugged when accelerating (at 45 mph and at 76-8mph). initially the check engine lights flashed after awhile the lights stayed on (after the car misfires, the lights stay on). it was my 2nd ignition coil, to find out the culprit, my mechanic switched up the coils. the car drives like it should now, it had that problem when i bought it. so now i have to get used to just stepping down and the car driving like it was built to.

this new issue has the CEL on and sometimes (not all the time) a "check gas cap" message pops up on the DIC, ill go to autozone and get a new cap and see if that fixes it

kschwed
10-20-12, 08:11 PM
the car chugged when accelerating (at 45 mph and at 76-8mph). initially the check engine lights flashed after awhile the lights stayed on (after the car misfires, the lights stay on). it was my 2nd ignition coil, to find out the culprit, my mechanic switched up the coils. the car drives like it should now, it had that problem when i bought it. so now i have to get used to just stepping down and the car driving like it was built to.

this new issue has the CEL on and sometimes (not all the time) a "check gas cap" message pops up on the DIC, ill go to autozone and get a new cap and see if that fixes it

That sounds similar to my problem, except that one night it started "chugging" really badly and the light started flashing. I replaced the coil and it hasn't happened like that since. But the initial small/light chuggle that has been there since I got the car 3 years ago is still there. I wish a light would come on when this happens.

buzz
10-21-12, 07:34 PM
I had a similar problem with my 2008 and had to replace two coil packs. I also discovered a TSB issued 7/1/2012 on this subject. Apparently, there is a problem with coil packs getting too hot and failing prematurely. I discovered this after paying a dealer to replace the packs and I intend to bring this up with the dealer.

kschwed
10-21-12, 07:45 PM
I had a similar problem with my 2008 and had to replace two coil packs. I also discovered a TSB issued 7/1/2012 on this subject. Apparently, there is a problem with coil packs getting too hot and failing prematurely. I discovered this after paying a dealer to replace the packs and I intend to bring this up with the dealer.

What is a "coil pack"? And how was this diagnosed?

truckinman
10-21-12, 08:02 PM
What is a "coil pack"? And how was this diagnosed?

By coil pack, he means ignition coil. Our cars don't have coil packs. They have what's called "coil on plug" ignition coils. A coil pack is where all the coils are grouped together in one pack. My fiancÚs Saturn has a coil pack.

kschwed
10-22-12, 12:34 AM
By coil pack, he means ignition coil. Our cars don't have coil packs. They have what's called "coil on plug" ignition coils. A coil pack is where all the coils are grouped together in one pack. My fiancÚs Saturn has a coil pack.

So possibly I have another faulty ignition coil..

truckinman
10-22-12, 03:52 AM
So possibly I have another faulty ignition coil..

It's possible. But it should be throwing a code if it's another bad coil. And not to mention, if youve been driving this thing for 3 Yeats with a miss fire, your catalytic converter should probably be just about ready to expire. If it's not already expired. But all those things should throw a code. I'd take it back to autozone, and just for sh'ts and giggles have them run another diagnostic and see if anything comes up.

But if it is a miss, more problems should have noticeably surfaced by now if it's been going on for 3 years.

kschwed
10-22-12, 10:49 AM
It's possible. But it should be throwing a code if it's another bad coil. And not to mention, if youve been driving this thing for 3 Yeats with a miss fire, your catalytic converter should probably be just about ready to expire. If it's not already expired. But all those things should throw a code. I'd take it back to autozone, and just for sh'ts and giggles have them run another diagnostic and see if anything comes up.

But if it is a miss, more problems should have noticeably surfaced by now if it's been going on for 3 years.

Well, I just had it smogged and it passed, so I think the cat is fine. Autozone doesn't do scans for free in California anymore. I ended up buying a small $90 scanner. No other codes were up except the cylinder 3 misfire when I scanned before. I agree though, that a miss would have caused more damage.

What is so frustrating is that it will go a week at a time without doing it. In fact, it probably hasn't done it in about 6 or 7 days now.

EChas3
10-22-12, 08:33 PM
Here in Wisconsin, smog tests just scan for codes. I'd bet your issue is fuel/mixture.

buzz
10-22-12, 08:45 PM
By coil pack, he means ignition coil. Our cars don't have coil packs. They have what's called "coil on plug" ignition coils. A coil pack is where all the coils are grouped together in one pack. My fiancÚs Saturn has a coil pack.

Actually, the term is "ignition coils", and is listed as such on my work order from 9/28/2012. On the 2008 V6, there are six of them. They did a diagnostic check and identified as #1 & #2 as failed. They swapped #1 for #5 and #2 with #4 and repeated the diagnostic test. This identified the two coils as being bad, so they were replaced.

truckinman
10-22-12, 09:25 PM
Actually, the term is "ignition coils",.


Isn't that what I said? Lol

kschwed
10-22-12, 09:36 PM
Here in Wisconsin, smog tests just scan for codes. I'd bet your issue is fuel/mixture.

Your suggesting that my issue is fuel?

I doubt that, but in all fairness, the thought crossed my mind. I always fill up at Shell, but this last week I filled up at a 76. It hasn't happened in a week. This is too strange.

buzz
10-23-12, 08:50 PM
Hey truckinman, it was just a clarification, such as bucket vs pail. I was trying to offer the gentleman a suggestion, and maybe used the wrong term. BTW, when the dealer called me and told me what they found, he referred to the problem with two "coil packs".

My problem was with surging and a distinct problem with power when climbing hills. I was expecting the problem to be transmission related, and it wasn't until I got a flashing engine light I thought it might be something else. For me, after the very expensive repair, the problem is gone! I am happy with the outcome.

I love this forum, and can say it has helped me with several issues over the years. Some suggestions have not been correct, and others have been spot on!

EChas3
10-23-12, 11:02 PM
Your suggesting that my issue is fuel?

I doubt that, but in all fairness, the thought crossed my mind. I always fill up at Shell, but this last week I filled up at a 76. It hasn't happened in a week. This is too strange.

I beg your your pardon. I do not suspect 'bad gas'. In these cars, an ignition issue will nearly always throw a code & set the CES light. If there are no lights & no codes, I suspect the air/fuel mixture. If you had a N*, I'd suspect loose intake manifold bolts. With a V6, I don't have much to suggest.

kschwed
10-24-12, 12:41 AM
I beg your your pardon. I do not suspect 'bad gas'. In these cars, an ignition issue will nearly always throw a code & set the CES light. If there are no lights & no codes, I suspect the air/fuel mixture. If you had a N*, I'd suspect loose intake manifold bolts. With a V6, I don't have much to suggest.

What is involved that can affect my air/fuel mixture? Or what is involved that I am able to check without a mechanic's involvement?

Thanks.

truckinman
10-24-12, 01:54 AM
Hey truckinman, it was just a clarification, such as bucket vs pail. I was trying to offer the gentleman a suggestion, and maybe used the wrong term. BTW, when the dealer called me and told me what they found, he referred to the problem with two "coil packs".



I love it when the tech, who is supposedly educated in the mechanical operation of our exact vehicle, doesn't even know what such a basic part as an ignition coil is called.

buzz
10-24-12, 02:14 PM
I love it when the tech, who is supposedly educated in the mechanical operation of our exact vehicle, doesn't even know what such a basic part as an ignition coil is called.

I know I am not "educated in the mechanical operation of the exact vehicle"; however, I am well educated. Keep in mind, the call was NOT from the actual "tech" doing the repair, it was from the service writer. A very nice guy, and I am sure he knows how to do his job; however, he is NOT doing the wrenching! In any case, the repair was done correctly and the problem is gone... at least that problem!

EChas3
10-24-12, 07:50 PM
What is involved that can affect my air/fuel mixture? Or what is involved that I am able to check without a mechanic's involvement?

Fuel filter? Air filter? Any intake mods? MAF (Mass Air Flow) sensor?

IMHO, if you're not experienced with these cars, you're better off taking it to a good dealer.

Mullah88
10-27-12, 03:58 PM
ok so my car stopped chugging at 45-48mph (changed ignition coil 2) but get up to 80-84mph, it chugs/stutters so i'm guessing coil 4 or 5 failed?

truckinman
10-27-12, 05:42 PM
ok so my car stopped chugging at 45-48mph (changed ignition coil 2) but get up to 80-84mph, it chugs/stutters so i'm guessing coil 4 or 5 failed?

I wouldn't think speed would have anything to do with which cylinder is miss firing. Could be wrong but I doubt that makes a difference

kschwed
10-27-12, 07:45 PM
I wouldn't think speed would have anything to do with which cylinder is miss firing. Could be wrong but I doubt that makes a difference

See, this is my confusion too. So I tried a different gas (I didn't really think this would make a difference, but I wanted to experiment) and it didn't make a difference. I thought it had, because I wasn't experiencing the surging for about a week, but then it started again, on the same tank. However, when it came back, it came back as more of a jolting than a hesitation like in the past. It feels more like a misfire now. I'm pretty convinced that I need to replace another coil, but I'm waiting for the CEL to come back on so I know which one. It would make sense that multiple would fail at once.

kschwed
12-20-12, 01:27 AM
So, nearly two months after replacing coil 3, my CEL came back on. It's coil 1 now. HOPEFULLY this is the coil that has been giving me all of the hesitations and stuttering. I ordered the part from autopartwarehouse.com - http://www.autopartswarehouse.com/sku/Cadillac/STS/AutoTrust_Platinum/Ignition_Coil/2006/Base/6_Cyl_3-dot-6L/WREPC504611ATP.html?intcmpid=Product+Listings+Best +Seller

Has anyone used this brand before? It's a 5 year warranty.

I also want to confirm where coil 1 is. It should be on the passenger side of the car, closest to the front of the car, or grille.

5 6
3 4
1 2

Like that?

Thanks.

truckinman
12-20-12, 05:13 AM
Yea sir you've got the coil positions correct

kschwed
12-23-12, 12:25 AM
Swapped out coil 1 with a new one. Running back to normal. I haven't really been able to determine if this has fixed the 20-30mph and 60-80mph stuttering yet, but I will report on that soon.

So just to be clear, I'm at almost 80k miles and I've had two ignition coils go bad in the last 5k miles. Anyone know why this is happening?

On a side note, how often should spark plugs be replaced and how involved is the process?

Ludacrisvp
12-23-12, 12:34 AM
plugs should be good to 100,000 miles under normal conditions... use OEM plugs ONLY.

kschwed
12-23-12, 11:17 AM
Any reason OEM only?

curtc
12-23-12, 11:22 AM
Any reason OEM only?

Cause the engine will puke them out if you don't.

kschwed
12-23-12, 12:12 PM
Clearly it won't "puke" them out, but on a serious note, only the OEM are compatible? This is a V6 if that makes any difference.

EChas3
12-23-12, 04:18 PM
N* is a bit fussy about plugs but they do usually perform well for over 100k. Many members report issues after using other than OEM.

Members do report coil failures with growing frequency at 80k miles. I expect cars exposed to greater ranges of environment would be more susceptable.

kschwed
12-23-12, 06:16 PM
I see. I'll go OEM then... not really a big deal. Can they be bought pre-gapped to the proper spec?

Also, what exactly causes a coil to go bad?

EChas3
12-23-12, 09:41 PM
AKAIK, coils' biggest enemy is moisture. Any tiny cracks allow moisture to short windings and/or lower the voltage and weaken the spark. IDK if that's also true with the STS coils.

kschwed
12-28-12, 10:45 PM
So I decided to take a look at the TSB's for my car again and came across this one:

Make : CADILLAC Model : STS Year : 2006
Manufacturer : General Motors LLC
Service Bulletin Number : 3456A Date of Bulletin :
NHTSA Item Number : 10017146
Component : VEHICLE SPEED CONTROL
Summary :
TCC SURGE, SHUDDER OR CHUGGLE ON LIGHT LOAD JUST AFTER TORQUE CONVERTER CLUTCH ENGAGEMENT WITH TRANSMISSION AT OPERATING TEMPERATURE. *SC

This sounds pretty similar to the issue I've been experiencing. Anyone have any idea what the next step in diagnosing this might be?

DarkMingBlueSTS
12-29-12, 11:05 AM
So I decided to take a look at the TSB's for my car again and came across this one:

Make : CADILLAC Model : STS Year : 2006
Manufacturer : General Motors LLC
Service Bulletin Number : 3456A Date of Bulletin :
NHTSA Item Number : 10017146
Component : VEHICLE SPEED CONTROL
Summary :
TCC SURGE, SHUDDER OR CHUGGLE ON LIGHT LOAD JUST AFTER TORQUE CONVERTER CLUTCH ENGAGEMENT WITH TRANSMISSION AT OPERATING TEMPERATURE. *SC

This sounds pretty similar to the issue I've been experiencing. Anyone have any idea what the next step in diagnosing this might be?

Is your CEL on or not? If its not I would lean more to the tc or it could be low on oil(mine kind of "bucked and jerked" when there was no oil in it).

kschwed
12-29-12, 11:40 AM
CEL is not on and the TC was replaced about 30k miles ago.

DarkMingBlueSTS
12-29-12, 11:45 AM
CEL is not on and the TC was replaced about 30k miles ago.
And all of those problems are gone right? How much was the replacement? Mine is failing too

orange57
12-29-12, 01:32 PM
Have you replaced your air filter and fuel filter yet? I had issues with a surging/shuddering when trying to accelerate at around 55-65mph on an older car. Replacing fuel filter and air filter help out. Also, you notice it at two different speeds, are the RPM's similar at those speeds when you notice it?

As others have said, if there is something internal to the transmission, it will be cheaper to replace the whole unit. I had an issue with my trans shortly after I bought the car where it would not shift into 4th. The cost to drop the trans and repair just 4th gear was about 50 bucks less than the cost of a whole transmission. I only had a short warranty when I bought my car that only covered up to $2000. The trans itself was around $1900 new from GM, so I purchased it and installed it myself. And the new trans came with a new Torque Converter.

I have seen rebuilt units for around the $1200-1500 range with no core charge too.

kschwed
12-29-12, 05:43 PM
And all of those problems are gone right? How much was the replacement? Mine is failing too

No, the torque converter was replaced around 40k miles for some minor shifting issues, right after I bought it. It was under warranty, so I really don't remember the cost.

----------


Have you replaced your air filter and fuel filter yet? I had issues with a surging/shuddering when trying to accelerate at around 55-65mph on an older car. Replacing fuel filter and air filter help out. Also, you notice it at two different speeds, are the RPM's similar at those speeds when you notice it?

As others have said, if there is something internal to the transmission, it will be cheaper to replace the whole unit. I had an issue with my trans shortly after I bought the car where it would not shift into 4th. The cost to drop the trans and repair just 4th gear was about 50 bucks less than the cost of a whole transmission. I only had a short warranty when I bought my car that only covered up to $2000. The trans itself was around $1900 new from GM, so I purchased it and installed it myself. And the new trans came with a new Torque Converter.

I have seen rebuilt units for around the $1200-1500 range with no core charge too.

I replaced the air filter at 50k miles, but I suppose I should check it. It might need to be changed again. I've never replaced the fuel filter. And yes, the RPMs are about the same at both speed intervals.

orange57
12-29-12, 06:07 PM
If it is the RPM, it could be Torque converter related, even though you had it replaced 30K miles ago. It seems there has been a TC problem on these cars. Hopefully, for your wallets sake, it isn't.

Fleetwood49
01-03-14, 12:19 PM
My cylinder #3 coil pack just went bad.
Dealer is going to replace it graciously for over $500.
If it wasn't 10 below zero, I'd do it myself.
Dealer said shop time was 2+ hours.
Does anybody know what the shop time is for this job, and can you send me something that documents that.
Sounds like this is pretty easy, take off intake, swap out coil pack, that's it.
Should be much less than 2 hours.
I hate DEALERS!!!!
Car is there right now, please help if possible.
I'm not afraid to tell the dealer they are full of crap, they have screwed up other repairs I've had done before.

curtc
01-03-14, 12:40 PM
2 hours for a coil swap??? Don't have any documents to back up my opinion but that is ridiculous! I'd say an hour MAX, and that's pushing it.

Fleetwood49
01-03-14, 12:51 PM
I called another dealer and asked for the shop time for that job and they told me 1.8 hours.
So maybe 2 hours isn't that far off.
Still seems like a lot.

curtc
01-03-14, 12:55 PM
Any competent mechanic should be able to tackle that job. I'd find the best independent shop you can with the lowest labor rates, no reason to take it up the rear at a dealer for something like that. Not to mention the coil itself shouldn't cost more than $50-$75, I'd say $200 tops for something like this. $500 is an absolute raping!

Ludacrisvp
01-03-14, 02:48 PM
i agree with curtc ... they are price gouging you.

KRSTS
01-03-14, 03:06 PM
You are being raped. I don't even have to remove the intake manifold on my 3.6 DI. I keep a spare in the glove compartment (cost me $45). I've had two fail so far and I don't want to continue to drive when the next one goes, because it is bad for the cats. Takes less than ten minutes to replace.

1BadCadSTS
01-03-14, 05:03 PM
You are being raped. I don't even have to remove the intake manifold on my 3.6 DI. I keep a spare in the glove compartment (cost me $45). I've had two fail so far and I don't want to continue to drive when the next one goes, because it is bad for the cats. Takes less than ten minutes to replace.

His 06 non di I know for a fact you cannot access all coils to replace. They require removal of the upper intake plenum to replace.

STSJr
01-03-14, 06:40 PM
**My #3 and #6 just went bad last week. I called my local dealer and they said it would be one hour of work maybe two. I brought my car to my local shop and he replaced the entire side coil pack for $400 + $85 for one hour of work. I also had him replace my spark plugs and intake manifold gasket that was leaking.

If I were you I would call a reputable local shop. They might do it for cheaper and have it done quicker.

DarkMingBlueSTS
01-03-14, 11:38 PM
The intake doesn't have to be completely removed for a 3.6, take out all of the bolts for it, remove air filter duct, gently lift and push intake towards the passenger side to access the driver side coils/plugs, do the opposite for the passenger side coil/plugs...very simple project

1BadCadSTS
01-04-14, 01:36 AM
The intake doesn't have to be completely removed for a 3.6, take out all of the bolts for it, remove air filter duct, gently lift and push intake towards the passenger side to access the driver side coils/plugs, do the opposite for the passenger side coil/plugs...very simple project

That's pretty bad advice. After time and heat cycles have made the plastic pcv line very brittle shifting the intake from side to side to gain access to the coils is just asking them to crack. Not to mention you should replace the plenum gasket when you dislodge it which requires its removal too. There's a reason why coil replacement the 1st step is remove the upper plenum. It's truly not that difficult and per your steps your I bolting it anyway. There's a right way to do things and a half ass way. There's a reason why the cost is high. It's the price of doing things RIGHT.

DarkMingBlueSTS
01-04-14, 05:35 AM
That's pretty bad advice. After time and heat cycles have made the plastic pcv line very brittle shifting the intake from side to side to gain access to the coils is just asking them to crack. Not to mention you should replace the plenum gasket when you dislodge it which requires its removal too. There's a reason why coil replacement the 1st step is remove the upper plenum. It's truly not that difficult and per your steps your I bolting it anyway. There's a right way to do things and a half ass way. There's a reason why the cost is high. It's the price of doing things RIGHT.

My car has over 200,000 miles on it, I'm sure all of the plastic is very brittle, and mine has no issues after spark plug replacement....ijs

clay2money
02-05-14, 06:58 AM
I have codes p0301, p0302, and p0690 suggestions?