: Engine "skips" during acceleration



burkewm
08-05-12, 12:28 PM
The other day I noticed something off with the car and am not sure of the cause. Background: 2009, 11k miles, new ZR rated tires, had the car ~3 weeks. When cruising along at a fixed speed (happened at 40, 50 and 60 mph on different occasions) I will try to accelerate slowly, and the car feels like it is skipping, gets stuck and wont accelerate. The RPMs don't change, and it only happens if I try to slowly accelerate... if I stomp on it, it will increase speed normally. At first I wondered if it was the tires, but it just doesn't feel like the tires are the reason... and I don't think they would keep the car from accelerating if I was pushing the pedal down. I've read all about the timing chains being an issue with my car (the 3.6L), and I'm worried that this might be a cause. Anyone else ever had an issue like this? Any ideas as to what it may be? I am going to take it into the dealer, but would like to have an idea of what might be wrong before I bring it in. Thanks for any help you can provide.

DarkMingBlueSTS
08-05-12, 12:47 PM
Mine does that too like when I'm trying to keep it at the current speed I'm running at(30-50mph) and when slowly accelerating but when I accelerate quicker it doesn't do it....some ppl on here have described it as a torque converter "shutter" or "chuggle" but idk if that's what it is

burkewm
08-05-12, 12:56 PM
That sounds like what might be the cause, you haven't taken it in or anything? Just don't want it to be something more serious and since I have a long warranty on the car (until late 2014 or 100k miles, 2014 sure to come first) I was thinking about getting it looked at.

DarkMingBlueSTS
08-05-12, 01:17 PM
No I haven't yet...lucky you on the warranty

MacMuse
08-05-12, 07:45 PM
Vacuum issue is a possibility. Lots of tubes and hoses on these engines and one or two not working properly caused a similar sensation with mine last year.

Mrsanders3960
08-10-12, 03:30 PM
My 08 STS did this, Before taking to the dealership I ran the current tank of fuel empty then dropped a tank full of 93 (no messages about premium being worthless please) from a brand name gas station, then a bottle of RXP carbon cleaner(http://www.rxp.com/) and the problem went away. A tank of gas and bottle of RXP is much cheaper than the dealer, and even if it doesn't work you were gonna need the fuel anyway.

burkewm
08-10-12, 05:18 PM
My 08 STS did this, Before taking to the dealership I ran the current tank of fuel empty then dropped a tank full of 93 (no messages about premium being worthless please) from a brand name gas station, then a bottle of RXP carbon cleaner(http://www.rxp.com/) and the problem went away. A tank of gas and bottle of RXP is much cheaper than the dealer, and even if it doesn't work you were gonna need the fuel anyway.

Thanks I'll give this a shot. Been fueling up at Sam's Club (cheaper, but not top tier). Guess I will start filling up with top tier and clean it on out. I do have whatever the issue is covered under warranty, but I might as well try this... at less than 1/8 tank right now anyways.

Submariner409
08-10-12, 05:51 PM
To sort of parallel Mrsanders3960, try a fill-up with Shell, Chevron, EXXON, Texaco, Philips 66 premium gasoline and a 20 oz. jug of Chevron TECHRON.

Google "top tier gasoline" and "chevron techron" to find out why.

burkewm
08-10-12, 10:22 PM
Yeah I checked out the top tier website a couple days ago. Techron has great reviews on Amazon too, will have to give it a go on my fill-up tomorrow and see what kind of results I get.

Mrsanders3960
08-11-12, 02:02 PM
I always hear about higher octane fuels being waste of money, however in my past i have had 2 cars ruined by cheap gas and ethanol. Since I have changed my fueling habits I have not had these troubles, and with the higher octane (93) I average 22MPG City and about 24 HWY in my 3.6 STS. (Now if go have a little fun all that goes out the window.)

KRSTS
08-11-12, 02:07 PM
I get that with Top Tier regular gas and a bottle of Techron every oil change. Where do you find gas without ethanol?

Mrsanders3960
08-11-12, 04:43 PM
I travel thru Oklahoma a lot and there are stations there without Ethanol. Its pretty difficult these days, especially in modern cities. Most Cities that are considered smog offenders by the gov require ethanol in fuel. Problem I have is that I had to pay the bill to repair damage done by the so called 10% ethanol.

dannyquest
08-11-12, 05:30 PM
Sound like a torque converter is going bad. Same thing my 06 STS was doing. It was out of warrenty. So the first line of attack the dealer want to do is down a program which only changes when torque converter locked up. At higher speed, 45- 50 mph. Some time you won't notice the chuggle. But that does't fix the problem. It will show up when the car is out of warrenty. I was lucky Cadillac split the cost with me. Danny

EChas3
08-12-12, 12:34 AM
http://pure-gas.org

burkewm
08-12-12, 10:54 PM
haha not one of those gas stations is within a hundred miles of me, hopefully the list keeps growing.

curtc
08-12-12, 11:19 PM
Apparently the Amcon station across town is ethanol free, maybe I'll start filling up there.

canam0530
03-06-14, 07:24 PM
I have a 2009 cadillac cts4 3.6 direct injected car. the car shudders and hesitates when driving down the road and from accelerating. I have had the car to the cadillac dealer 6 times. the first two times they did a carbon clean out. after the carbon clean out they replaced some spark plugs. when i got the car back the third time it was still doing the same thing, since then i have had the spark plugs changed again, the injectors replaced the fuel rail system replaced the cadilatic converter replaced and coil pack replaced. the car is still doing the same thing not to menetion my gas mileage is horrible. im fed up with this car, any ideas or suggestions please

CadiTamer
03-06-14, 07:44 PM
That's what my car did when the torque converter began failing. Ended up swapping the entire transmission because the fluid had never been changed in the 126K miles on the car. Problem went away.

Cadillac Cust Svc
03-07-14, 03:18 PM
I understand your frustration due to your current situation, canam0530 and apologize for any inconvenience this has caused. Please feel free to send us a private message that includes your full contact information, VIN, current mileage and dealership name and location so we can further discuss your situation. We are more than happy to contact your dealership on your behalf to discuss the outcome and document your concern and comments within our system which can be accessed by multiple departments at General Motors.

Sincerely,

Laura M.
Cadillac Customer Care

EChas3
03-07-14, 11:06 PM
Have you checked your oil level? If that is right, I'd be surprised if it isn't a coil.

malatu
03-09-14, 03:30 PM
I always hear about higher octane fuels being waste of money, however in my past i have had 2 cars ruined by cheap gas and ethanol. Since I have changed my fueling habits I have not had these troubles, and with the higher octane (93) I average 22MPG City and about 24 HWY in my 3.6 STS. (Now if go have a little fun all that goes out the window.)

Do a little reading on what a higher octane fuel is, why it exists and what role it plays in an certain engines (high compression). If you bring yourself to an understanding those concepts, you will be able to make an informed decision as to why you should or should not use higher octane fuel in any particular engine.

Most often in life, the more more expensive something is, the higher the quality. This is not the case with higher octane fuel! Higher octane fuel is not better fuel, it's just a different kind of fuel. There are lot's of posts here explaining such. Check em' out.

Daves_05_STS
03-23-14, 10:08 PM
With regard to OP:

Same issue w/my 05 3.6 RWD. I'll get a check engine flash [always goes away after 30 or so seconds] but, 2x she threw a P0305.

I like to think this is not the Torque Converter issue.

I only buy gas at Shell. Did the Chevron Techron thing.
Coil pack on the way along w/OEM .43 gap plugs.

My question: Can I get to coil pack 5 without having to do the entire 'tear down'? I'd rather just do the coil pack now, all plugs when it gets warmer. My idle is fine btwn 620-630 and as long as i bby the throttle all rides nice.

Thanks & BTW the above woes all started after I replaced the paper air filter with a K&N. I was not pleased with the filter fit [flimsy silicon frame vs. rigid plastic]
I took the entire air box out and made sure the filter was seated properly.

Neutrocuted
03-24-14, 08:51 AM
I have the same thing going on, no codes, and I use premium from Sam's. I also notice occasional mild engine stumbles while idling in gear at a stop light. Guess it's time for some top tier and some cleaner!

KRSTS
03-24-14, 11:44 AM
Why would you use "premium" in a 3.6 ?

C&C
03-24-14, 12:34 PM
Post #22 'Daves...' Since your problem can be related to installing the K&N:

While not rampant (I've used K&N and have never had a problem), but if the filter is over-oiled and through induction some of that oil leaves the filter and gets onto the MAF sensor, you may experience some drive-ability problems. They make a MAF sensor cleaner that you may want to try (making sure the filter isn't yielding any oil in use).

EChas3
03-28-14, 11:17 PM
The OEM filter flows better and protects your engine better and cheaper than K & N.

malatu
03-29-14, 10:43 AM
Why would you use "premium" in a 3.6 ?

It costs more so it should be better for my car, right? :stirpot:

STS 2005
04-02-14, 01:15 PM
For the 6 cylinder you can get to number five easily by just pulling the top shroud, couple bolts to take off under that but easy. I did the coil pack and plug when i was getting the code and dash light flashing under accelerating hard. It helped for a while but the problem came back..

Number five is rear by the passenger side

Daves_05_STS
04-05-14, 07:40 PM
THX STS 2005. I removed the top shroud/cover just earlier. Aside from one harness, CYL5 on the 3.6L is practically looking at you.

....also thinking about ditching the K&N air filter.

Coil replaced: 10 mins and a 10MM socket = NO MORE FLASHING CEL AT HARD/GRADUAL ACCELERATION!!
I left the K&N air filter installed as that would have been a poor troubleshooting technique.
...now if i could only get my gas mileage back up to 19.9MPG [from this pathetic 19.1]

Cheers