EGR Valve Info

I wanted to post this message for the GP owners that have had some of the same problems I have had.

I was getting random misfires as well as cyl 2 misfires and sometimes cyl 4 misfires. I cleaned the injectors proffesionally.....and it helped...but did not fix the problem. The car also had a very rich smell at the exhaust....as well as would suck occassionally almost like a valve was burnt. This would only happen at idle far as I could tell.....but it was driving me nuts. With the advice of Bnaylor and Richtaz and a good scanner I was able to get down to the EGR valve being the problem. I ordered an OEM EGR from gmpartsdirect.com (excellent price.....LONG time shipping.....2 weeks till I got the EGR...but WELL worth the wait...I reccomend these guys to anyone.....just do not be in a hurry...)....and low and behold...the problem has gone away. I DID have to reset the computer on the car.....and then(after running like crap for about 5 minutes) the problem went away....and took about 20 minutes driving for the computer to relearn I had a new egr valve by the way. Guess if I had waited longer the car would have eventually figured it out for itself.

Anyway...thats all....I just wanted to pass this along to the forum since I chased this freakin' problem for about 3 months (and not just replacing parts at random to figure it out) and I don't want anyone else to suffer through it like I did.

Thanks to BNaylor and Richtazz as well as the rest of the forum for all the help.......You guys are the best...

Thanks for the update and feedback Ernie. Glad we could be of help to you. :bigthumb:

BTW - Don't forget about the Good Samaritan thing we discussed in the past. :lol:

No problem Ern, that's what we're here for. Helping people fix their own car and save $$$ is what this forum is about. People like Bnaylor, GTP dad (the best moderator on AF in my opinion, you RULE Lynn!!!) , LMP, KustomKid (when he's around, we miss you buddy!), just to name a few, make the Grand Prix forum kick booty!!!! Glad you got her fixed, and thanks for the feedback. We like to hear when it works out good.

Ernie, next time try going through Rich on the GM OEM parts. You will not be disappointed. His prices are as good as GMPARTSDIRECT and shipping costs are a lot more reasonable. I just took delivery of some miscellaneous GM parts for my son's Alero and got them in under 7 days, UPS ground. He's da' parts man!

Ernie, next time try going through Rich on the GM OEM parts. You will not be disappointed. His prices are as good as GMPARTSDIRECT and shipping costs are a lot more reasonable. I just took delivery of some miscellaneous GM parts for my son's Alero and got them in under 7 days, UPS ground. He's da' parts man!

Will do Bob. Matter of fact.....I need some stuff now....

I WILL do what ever I can to help out the forum. Feel like I have made some good friends here.....and will be sticking around.

Oh yeah.....and I left out GTP Dad on the thank you list.......thanks to you too. Your help is appreciated. Now.....can you guys make it rain before our whole state burns up??? LOL

Bonus prize fellas.......I find this morning that my milage has gone up about 5 -8 miles a gallon since the EGR change out. I did not expect this. I was hooking pretty good today too.......85mph on cruise.....so no cheating by being easy on the car...... That sure makes the price of fixing the car worth while. Hummmm....wonder how much more differance it will make to change out those 2 o2 sensors??

Bonus prize fellas.......I find this morning that my milage has gone up about 5 -8 miles a gallon since the EGR change out. I did not expect this. I was hooking pretty good today too.......85mph on cruise.....so no cheating by being easy on the car...... That sure makes the price of fixing the car worth while. Hummmm....wonder how much more differance it will make to change out those 2 o2 sensors??

Sometimes it is better to leave well enough alone but then again we are always searching for ways to make our cars better. If you have a lot of mileage on your GP and the 02 sensors are the originals then it is a good idea. It won't hurt. Just stay with the AC Delco OEM (AFS 109 front and AFS 141 rear). Ebay has the OEM AFS141 for $35.00 plus $6 shipping buy it now. The AFS 109 is hard to come by but I'm quite sure Rich will give you a good deal.


http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1,1&item=8019396201&sspagename=STRK%3AMEWA%3AIT

Cool....thanks Bob. YEp....got 188,000 on her....prolly would not be a bad idea to get both 02 sensors. Have you heard that an EGR would make that big of differance in milage? I am really amazed it would

Cool....thanks Bob. YEp....got 188,000 on her....prolly would not be a bad idea to get both 02 sensors. Have you heard that an EGR would make that big of differance in milage? I am really amazed it would

Oh yes. It your case it was stuck open routing 10 - 15 % of the exhaust gases back into the intake system when it should not have. The EGR valve only works under certain engine and emissions conditions not all the time as others have claimed. :screwy:

Actually it doesn't function and is inhibited until the engine gets up to 167 degrees F or 75 degrees C.

Well....I'll tell ya what. The wife is happy that my little orange box has paid for itself now. She was having some pretty big issues with me not getting this thing fixed right of the bat. Guess she figured the box would tell me more than it does. I explained that it "helps" find the problem. And at 75.00 an hour for a mechaninc to diagnose problems.....not fix them.....I got off easy far as I am concerned. Could not have done it w/o you and this forum though. As they say...information is power. Just gotta know where to get it!

Hey.....I think it is gonna rain. You guys are miracle workers! LOL

Are your mileage numbers based on hand calcs? How many miles do you have on the car since the EGR valve replacement? If you were averaging around 20 before hand, an 8mpg increase is a 40% gain. That is HUGE and almost too big of an increase for an EGR valve replacement.

Are your driving conditions the same as before you fixed the EGR?

I'm not trying to say you're wrong or anything, but when it comes to fuel economy you really can't base much on 1-2 tanks. Also whenever we replace something we're always telling ourself it is better so eliminating that bias with real hard numbers is the only way to do a solid comparison.

Are your mileage numbers based on hand calcs? How many miles do you have on the car since the EGR valve replacement? If you were averaging around 20 before hand, an 8mpg increase is a 40% gain. That is HUGE and almost too big of an increase for an EGR valve replacement.

Are your driving conditions the same as before you fixed the EGR?

I'm not trying to say you're wrong or anything, but when it comes to fuel economy you really can't base much on 1-2 tanks. Also whenever we replace something we're always telling ourself it is better so eliminating that bias with real hard numbers is the only way to do a solid comparison.


Basically....I drive about 850 miles a week. I am basing it off of going to and form work for 2 days......and it is about 70 miles here and back.....95% highway miles.....so yeah...not off of several tanks...but the car consistantly gets about 300-320 miles out of a tanks lately..(yeah I know....thats pretty bad) and used to get close to 400 miles to a tank. It seems that the car is back to where is was originally now. I did pull some weight of the car on Monday too....and I am sure that doesnt hurt. But.....it seems that the car had some real problems with emmisions because the smell coming off the exhuast smelled VERY rich....and burned your eyes. That smell is gone....not really any smell now. I would even get the rotton egg smell before on occassion.....and not while tromping the gas...just driving normal. That has ceased as well. So anyway......looks like thigs are much better now....and I will post any new findings asap.

Well....I'll tell ya what. The wife is happy that my little orange box has paid for itself now. She was having some pretty big issues with me not getting this thing fixed right of the bat. Guess she figured the box would tell me more than it does. I explained that it "helps" find the problem. And at 75.00 an hour for a mechaninc to diagnose problems.....not fix them.....I got off easy far as I am concerned. Could not have done it w/o you and this forum though. As they say...information is power. Just gotta know where to get it!

Hey.....I think it is gonna rain. You guys are miracle workers! LOL

Lol. :lol: Just tell her the scanner will pay for itself in the long run. Plus your friends and other family members will really like you too especially after you start helping them save money after they get a SES/CEL light. I lost count of the free beer I've received. My inlaws treat me differently now.

Lol. :lol: Just tell her the scanner will pay for itself in the long run. Plus your friends and other family members will really like you too especially after you start helping them save money after they get a SES/CEL light. I lost count of the free beer I've received. My inlaws treat me differently now.


Uh...yeah. I spend a good but of time in Auto Zone....and the freakin guys in there have the baby scanner...so all of the time I end up plugging in to cars up there to "help a brutha out". I feel sorry for them cause I was in thier shoes so long.

Haven't got the free beer yet.....but...hummmmmm Hehehehehe

AFS109- $65.16
AFS141- $59.19

for anyone else reading, shipping varies by zip code, I have your zip ern, about $8 to you. Same shipping time as other stuff we discussed before.

AFS109- $65.16
AFS141- $59.19

for anyone else reading, shipping varies by zip code, I have your zip ern, about $8 to you. Same shipping time as other stuff we discussed before.


Excellent. Thanks Rich. Better let my wife cool off for a bit....then...I can do it.

She informed me yesterday that I spent 750.00 last month on my car. I said..."hey...thats just 2 car payments..take your pick..make payments or make repairs..what do ya expect? :)