: Went to a mechanic today on EGR



laurieH
01-06-04, 05:24 PM
HI,

I went to the mechanic to see about my car and was shocked at the price they wanted to repair it. I can't get my car in til Thursday to get the work done so I figured I would use this time to see if this is a fair price.

The mechanic said my EGR valve is clogged and can't be cleaned (they didnt even try) he said the cost for replacing it would be $450 including labor. Also told me I should go ahead ane replace spark plugs and wires and that would be another $400. He said he wouldbe using the more expensive plugs and that the wires are expensive. I called around and that seems to be the case but I am not sure if I need new wires???? How can I be sure , they were replaced about 2 1/2 years ago and I am not sure if that eally needs to be done every 3 years or not. Anyone got any advice for me??? He also talked about doing a cleaning on the whole engine that would run about $219 and I wasnt even ready to hear about that. One other question, Don't I need to worry about maybe having a clogged aminfold or something since this valve is so clogged, I mean something must have casuedthis to happen or is this common over time???? I just wanted to see if I am crazy thinking this sounds like alot, I hate spending 800-$900 and maybe not having my problems fixed. Right now my car problems is obviousl my check engine light is on and I am gettgin a code of P036 meaning pintle position out of range adn my car seems to be lacking some power and hesitant at times. This all started one day following a $2200 oil leak fix. They replaced two gaskets and replaced bolts and engine brackets that were broke. Not even 24 hours later I had an engine light on and this problem, I am frustrated.

Thanks
Laurie

Logandiagnostic
01-06-04, 05:53 PM
Extremely common to have electronic GM EGR valves carbon up. About 70% can be repaired by cleaning the actual valve. That does not mean the internal parts of the engine need to be cleaned. If the problem persits the EGR tubes may need to be cleaned. I assume you are getting a code for a EGR malfunction.

The mechanic is wrong. Most electronic EGR valves can be saved by cleaning. If a new valve is needed....maybe about $150 for a new EGR valve if you shop around.

The valve on the Northstar is a pain to get to. The EGR bolt shares a fuel line bracket. This is the hassle...most GMs its a 10 minute and 2-3 bolts to get out.

Because the EGR is for 'exhaust gas circulation'.... I would think in most cases sooner or latter all the EGR valves will have to be cleaned. Its a valve that is basically sitting and routing exhaust gas. Dirty stuff.

Heres a picture of the EGR valve on a Northstar. Its the black round thing. Hopefully it does not look like $500.

http://images.andale.com/f2/115/106/3768672/1074320007722_egr.jpg

Logan



Logan

zonie77
01-06-04, 10:46 PM
GM was having a problem with carbon chunks coming loose in the EGR passages and sticking in the EGR valve. Very common on S10 Blazers. They later reprogramed the EGR to completely open momentarily on startup to release any chunks, Voila! problem solved. It sure sounds like a chunk of carbon in the valve keeping it open. Removing and cleaning should (should, things are never 100%) fix it.
The problem is he wants to sell you a new EGR valve, they may have had a few that really did need changing. Do you know anyone who can do the work for you? Or are you qualified? The work you need done isn't too hard and you'll save a lot of money. None of this is real hard.

zonie77
01-06-04, 10:52 PM
I forgot to mention the work just done...Not sure which gaskets they replaces. If they took the intake manifold off they opened the EGR passages and didn't clean them so they caused the problem. If they didn't take the manifold off they may have indirectly caused the problem but pretty hard to get them to pay.
Which gaskets did they change?

ellisss
01-07-04, 01:16 AM
The mechanic said my EGR valve is clogged and can't be cleaned (they didnt even try) he said the cost for replacing it would be $450 including labor.
He's lying. I have never, in my almost five years as a Cadillac technician, seen a clogged EGR valve on a Northstar that couldn't be cleaned with enough effort.

$450 sounds about right for an original replacement EGR valve and the labor (about an hour) to install it. Sadly, Cadillac parts are expensive.


Also told me I should go ahead ane replace spark plugs and wires and that would be another $400.
Another lie, in my opinion. If you had bad plugs and wires, your Northstar would be setting misfire codes which would be shown on a scan tool. Also, $400 for plugs, wires, and labor on a Northstar is a little high.

If your plugs are fouled, but not worn, they can be cleaned. If you wires are old, but not failing, they are still functional and do not require immediate replacement.

It seems to me that you are disregarding my past suggestions to you completely. Does it make a difference if I tell you I'm used to dealing with the exact situation you are stuck in presently?

The Northstar motor has problems with carbon. It was this fact that led me to post an extremely long (and boring) post about carbon and how to deal with it. I'm thinking that my mistake was not putting enough emphasis on the easiest solution to carbon build-up in the Northstar's EGR system. Well, here it is:

Cadillac dealers offer a service that will, (if done properly), remove all traces of carbon from the intake system, EGR system, combustion chambers, and piston ring grooves. This service will give you a clean slate, so to speak, as far as carbon is concerned. After that, you will need to modify your maintenance habits, and possibly your driving habits, if you are doing things that encourage the formation and accumulation of excessive carbon build-up (maybe you can read about this in my thread on carbon and how to deal with it). The service I'm refering to was designed specifically for the Northstar engine. It's not cheap ~~ about $350. It works, and it works wonderfully. It entails removing your spark plugs while the motor is hot, and filling the cylinders with a chemical (that, by the way, isn't GM's Top Engine Cleaner). After a soaking period, the motor is evacuated by sucking the cleaner out of the cylinders. Next, the EGR valve is removed, and a special adapter is bolted on to the motor at the EGR flange. More chemical is forced through the motor while it's running. Finally, to finish the procedure, another chemical is used to clean the carbon from your throttle body and intale plenum. This entire procedure, (again, if done correctly), is totally harmess to spark plugs, exhaust systems, and oxygen sensors.

I'm no longer employed by GM, so I can't offer you the specific TSB number where this procedure is covered in detail. I can assure you that your local Cadillac dealer is quite familiar with it.


Anyone got any advice for me???
Yes, but it feels like I'm repeating myself. :banghead:

Possibly the most important suggestion I had for you was to bring your car to a trusted and honest mechanic. From your description, the place you're bringing your car thinks you're some dumb chick with an endless supply of money to fix her car.

I suggest (:banghead: ) that you no longer allow this place to fix or even maintain your Cadillac.

Maybe you can talk to friends and family, and find out if they have any positive experiences with local shops. Also, you can walk into a local Cadillac dealer and explain your situation. Tell them you aren't willing to put up with mechanic shops ripping you off, and you're interested in the engine cleaning service that is specifically for your Northstar motor. Tell them you don't want to buy another EGR valve, because it isn't necessary... your old one can be cleaned just fine. Be nice, bring a couple of boxes of cookies or doughnuts with you. Tell them that if you're happy with their honesty, integrity, and service... that you'll allow them to do all your repairs and maintenance in the future. (you don't have to make good on that claim, just say it to provoke them into putting an extra effort into pleasing you presently.)

Spend the money on the cleaning service I've suggested here. Read my other post to see if there are any changes you can make to your driving and maintenance habits that will help prevent the build-up of carbon in the future.

If you, or anyone else, can read what I've written here and think these aren't good suggestions... then I give up. :banghead: :banghead:


One other question, Don't I need to worry about maybe having a clogged aminfold or something since this valve is so clogged, I mean something must have casuedthis to happen or is this common over time???? Yes, you need to worry about carbon build-up anywhere in your upper engine and intake system. Yes, there are a couple of things causing this... first is the fact that all engines produce carbon deposits in multiple ways and in many places. Second is that there are some poor driving and maintenance habits that contribute to the formation and accumulation of carbon in your motor. Third is that the Northstar engine has many problems that are due to carbon build-up.


my check engine light is on and I am gettgin a code of P036 meaning pintle position out of range adn my car seems to be lacking some power and hesitant at times. You have carbon in your EGR system (not just the EGR valve) that is getting stuck between the EGR valve's pintle and it's seat, causing it to stick open.

Replace the EGR valve and the carbon that is still there (in the rest of the system) will eventually break free and you'll be back at square-one. Clean the motor so it's completely free of carbon in the intake and EGR systems, and if you don't propery maintain the motor, the carbon will re-appear in mass quantities and you'll still be back at square-one.

:banghead: :banghead:


I am frustrated.Yeah... I know the feeling.

Honestly, though ~~ I'm doing my best, as someone who is intimately familiar with both the problem you're having now and the Northstar engine itself. I'm trying to help you.

Good luck. :yup:

--
Ellisss.

Logandiagnostic
01-07-04, 02:15 AM
As mentioned.......you cannot avoid carbon build up in the EGR system. Its the nature of the beast per say.

I personally feel the 'Cadillac carbon treatment' @ $400-500 bucks a pop can be avoided.

This is a post from a Cadillac Northstar engineer...it is taken from another website....not a direct quote...

"Cadillac: 2003 deville

The subject of oil consumption really does not have a "final" answer. The fact is that there is some variability in oil consumption in all production engines....regardless of who makes them on which continent. All the manufacturers recognize this and virtually all of them will call oil consumption as great as 1 quart in 1000 miles "normal" "acceptable" "allowable" "within production tolerances" etc.... This doesn't mean that all engines will get 1000 MPQ or that the engine was designed to get 1000 MPQ...it just recognizes the fact that there are going to be some engines that get 1000 MPQ that will be perfectly fine upon disassembly and will have nothing "wrong" with them.

The variables that usually enter into oil consumption are primarily associated with the piston/ring/cylinder bore. The number of valves or type of valve actuation has little to do with it.

The single biggest variable and the one that haas been discussed at great length on this forum is the cylinder bore finish or the cylinder honing pattern. The higher perfromance the engine is the more attention must be paid to the honing pattern and retention of oil on the cylinder walls to lubricate the piston and rings at full load , high RPM operation. The Northstar engine uses a very agressive cylinder bore finish that tends to retain a lot of oil to protect the piston and rings. When the blocks are honed at the factory there is a tolerance in the bore finish due to the fact that the honing stones will wear and need replacement. A brand new stone gives a slightly more agressive pattern than a "used" stone....so a block honed with new stones will have a more aggressive finish and most likely will use more oil.

Another variable is bore roundness. Like it or not, the bores tend to "move" slightly as the engine heats up and cools down and bolt tensions relax, etc. over time. All this contributes to slight bore out of roundness that is not bad or good...just different.

Carbon buildup in the rings and reing sealing are also variables that come into play with breakin, operating schedule, type of oil used, etc.

The one thing that I can attest to is that many, many customer oil consumption complaint engines have been torn down with absolutely nothing wrong found. The engines are often reassembled and put into test cars and driven by the engineers and more often than not the high oil consumption does not repeat itself !!! The single biggest common cause seems to be breakin...or lack there of. Many, many oil consuming NOrthstar engines are "fixed" by some full throttle operation. I often joke about "driving it like you stole it" but it really is no joke. The Northstar engine was designed as a high performance engine to be run hard and fast. Those that are run hard typically exhibit excellent ring seal, little carbon build up and good oil economy. We have seen engines with tens of thousands of miles on them that the rings have not sealed or mated to the sides of the ring grooves because the operating schdule was so light duty. The moral here is to flog it .... often.

In any case, the nice thing about the engines with the more aggressive honing pattern is that the pistons, rings and bores will last forever. It is very common to tear down a 200,000 mile Northstar engine and still see the original honing pattern in the cylinders. There is never any sign of cyilnder wall wear and the idea of a wear "ridge" at the top of the cyilnder bore is something that is laughable on a Northstar.

The other nice thing about a little oil consumption is that it adds tremendous safety factor to the oil change interval. Nothing could be better for the engine than an occasional quart of fresh oil. You can take the worst oil on the market and add a fresh quart every 1000 miles and over the life of the engine the wear will be better than an engine run on the best oil with no adds between changes.

While no one in the engineering commumnity wants high oil consuption the fact is that there is some variability in the oil consumption of an engine manufacturered at the rate of 1200 per day. The specs of what is "normal" simply reflects this...it does not imply that all engines whould get this or that somthing is wrong with and engine that gets more or less oil consumption.

There have been a lot of engineering changes over the years on the Northstar aimed at reducing the overall oil consumption and reducing the variability in the oil consumption of different engines. Many changes have been made to the honeing process to make it moe consistent. Changes to the piston and ring groove treatment have been made to make it more resistent to wear, poundout and microwelding at low oil retention rates. Regardless, there is still some variability.

One other thing that affects oil consuption, or the customers perception of oil consumption, is the move toward longer and longer change intervals. With the allowable change interval reaching as high as 12,500 miles on a 2003 Northstar if the oil life monitor is followed this could mean the addition of 3,4 or 5 quarts of oil to a very healthy engine. If the owner changes thier oil every 2000 or 3000 miles, despite the oil life monitor recommendations, then they would not have to add any oil between changes. The oil consumption is the same....the amount added between changes is all that is different. Yet, many customers do not make the distintion. Field surveyr repeatedly show that "acceptable" oil onsuption means "not having to add between changes"...whatever MPQ that is...???

The issue of oil consumption is very emotional , too, as many people perceive higher oil consumption as 'poor quality" or an indication that something is wrong. Blue smoke, fouling plugs, noise, etc...is a sign of something wrong. Using 1 quart in 1000 miles might be perfectly normal for an engine that has the high limit "rough" hone finish and is perfectly in spec...yet it will be perceived differently.

The Northstar engine in particular was designed to be a high performance engine and to perform well at high speeds and high loads. The engines are tested at loads and speeds for time periods few customers will ever be able to duplicate. It is unfortunate that the engineering that goes into making the engine capable of such running wometimes contributes to more oil consumption...especially as the produciton machining tolerances are taken into account.

Hope this helps rather than adding more fuel to the fire...so to speak."

Bxxxxxxxx

***---REPLIED TO MESSAGE BELOW---***
I have read a lot of post about Northstars that do consume oil (1 quart per 2000 miles for mine). My uncle also has a 98 Deville and he claims his does not burn any oil, Just curious if there are many northstars out there that do not burn oil?

Thanks.

ellisss
01-07-04, 02:55 AM
Excellent, excellent post, Logandiagnostic. I looked for a smiley that was doing a standing ovation, but there isn't one. :)

I agree with you, that the expensive cleaning procedure offered at the dealership can be avoided. I also think the procedure is an easy way to _quickly_ clean things up. A Northstar that is 'babied to death' can be revived by cleaning and an occasional WOT run. (heck, if someone has the time to wait... the cleaning isn't even necessary, I suppose.)

Funny how a '96 2.2l Cavalier (one of my cars, motor completely rebuilt from block to radiator) can go 5,000 miles without consuming a drop of oil (all with no WOT runs or extravagent maintenance)... but it's somehow okay for a Northstar driven by someone's Grandmother to burn a quart every 1000 miles? Hmmmm, I wonder what's up with that. :confused:

As far as the Northstar engineer goes, I'm sure that some of what he said was a matter of covering the brand's behind, so to speak. For instance:

---
The other nice thing about a little oil consumption is that it adds tremendous safety factor to the oil change interval. Nothing could be better for the engine than an occasional quart of fresh oil. You can take the worst oil on the market and add a fresh quart every 1000 miles and over the life of the engine the wear will be better than an engine run on the best oil with no adds between changes.
---

There is no basis in fact for the above statement. If you are aware of any, or can provide a link to some kind of study that would back that statement up, I would appreciate it.

My experience with Northstar engineers, (I've had conversations with three of them over the phone while diagnosing various problems), is that they will eagerly spout anything under the assumption that they are all highly educated and experienced... and the Northstar's technology advantages alone are enough argument to refute even the most basic and tested theories of automotive science.

Still, the post you made contains a whole bunch of great information.

--
Ellisss.

Logandiagnostic
01-07-04, 03:07 AM
Dont kill the messanger as they say....


Maybe you should start a car company.....



The bottom line on this post is shes about to get screwed on a fairly simple EGR repair. Yes, its clean the EGR and see if the issue comes back. Yes, a new factory GM EGR valve can certainly be found for around $150.

Yes, if the code comes back she may have to have some EGR tubes cleaned.

We clean EGR valves alllll the time. Its very rare that the customer has to come back and have tubes cleaned. True, there has been a couple of GM V6s where this was the case. Never on a Northstar.

Logan

laurieH
01-07-04, 03:24 PM
Thanks everyone for your replies, Ans I appreciate the long but informative response on carbon build-up. I hear ya, I really do. I asked yestreday about that and was told they did it for $219 and that it would clean things up very well in my car but wouldn't help the egr valve. I am planning on taking it to get the cleaning later this month after I get my valve fixed. I am a womans ans yes I get aot of crap from these car shops thinking I am ignoranat which I am not. No I am not a mechanic and I don't know everything but I can do simple repairs on my car adn I read alot and investigate always befre doing car work,I am sure I have been taken advantage of in the past but am really trying to avoid that again. I am checking on having someone try to clean my valve. I am thinknig that may do the trick like you all say. If not than maybe I can buy the part adn have someone put in on. I would do it but the fuel line kinda scare me and I don't want to mess anything up. I located it on my car and I see the two 8mm bolts and it looks fairly easy, maby I should go for it. I read the thread about cleaning it and think that part I can handle too. Anyway, thanks everyone and I will let you know how it goes. I love this site wish I would have found it about 2 years ago and a few thousand bucks ago!!!!!!!!!



Laurie (a smart blonde :))

st

ellisss
01-08-04, 12:09 AM
I asked yestreday about that and was told they did it for $219 and that it would clean things up very well in my car but wouldn't help the egr valve.
If you are planning on getting some kind of cleaning service anywhere but a Cadillac dealer... then I can say for sure you won't be getting the right one.

As I already wrote (:banghead: )... the cleaning tool kit that was designed by Cadillac has an adapter that bolts directly to the EGR flange and removes carbon from the entire EGR system. The shop you are going to has some kind of generic cleaning kit that won't help very much at all.

:banghead2 :banghead:


I located it on my car and I see the two 8mm bolts and it looks fairly easy, maby I should go for it.
They are M6 studs with 10mm heads on them. A 10mm socket, (one side may need a deep socket) will work fine.

I do not suggest you tackle this yourself. You won't know how to clean the valve... and if you make a mistake it's possible to cause problems.

Did you at least take my advice about cookies or doughnuts? :bonkers:

--
Ellisss.

mike98c
01-08-04, 08:00 PM
If you are planning on getting some kind of cleaning service anywhere but a Cadillac dealer... then I can say for sure you won't be getting the right one.

As I already wrote (:banghead: )... the cleaning tool kit that was designed by Cadillac has an adapter that bolts directly to the EGR flange and removes carbon from the entire EGR system. The shop you are going to has some kind of generic cleaning kit that won't help very much at all.

:banghead2 :banghead:


They are M6 studs with 10mm heads on them. A 10mm socket, (one side may need a deep socket) will work fine.






I do not suggest you tackle this yourself. You won't know how to clean the valve... and if you make a mistake it's possible to cause problems.

Did you at least take my advice about cookies or doughnuts? :bonkers:

--
Ellisss.I have cleaned a couple of the valves. You need to get all the old gasket (silvery material) off the valve and manifold with an actual store bought gasket scraper brfore you put the new gasket on so as not to scratch the seating surfaces and you can't let the carb cleaner run into the black can on top of the valve or you can ruin the windings on the motor.
The valve passages can be cleaned with a solvent resistant brush like a gun cleaning brush from Wal-mart or wherever. The valve should move freely against the closing pressure on it without binding and the head off the stem should of course seal against its seat in the base of the valve with no carbon buildup to interfere.