EGR Valve Replacement - Help Appreciated - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

ss ZHO · 06-22-2010, 04:44 PM

I have been living with my check engine light for too long in my 1999 Z28 (LS1). I never noticed an issue with performance, but its just annoying. Time to fix it.

OBD codes are:

P0405 - EGR system fault - ECM detected the EGR position sensor voltage was too low.
P1404 - EGR valve stuck open condition - While monitoring the EGR valve pintle position the ECM detected the closed position sensor voltage higher than the learned closed position voltage.

The probable cause that both codes have in common is a failed EGR valve.

So at this point, I am thinking of replacing the valve (I may try cleaning the existing one first).

My questions are:

How hard is it to replace EGR valve? Anyone have directions? (I heard its on the back of the intake manifold, but that area is buried in the engine bay, and I don't see how I can reach it).
Anyone else have these codes or a similar problem? What was the fix?

Thanks in advance.

02 WS6 TA · 06-22-2010, 04:57 PM

Couple suggestions...

If it were me (and it is, as I have three '00 LS1s which I have gone this route with) I'd simply remove the EGR entirely, plug the hole in the manifold (or upgrade to an LS6 or FAST) and have the reporting for the EGR circuit turned off in the PCM via HP Tuners or similar. You'll still skate thru smog, and see a slight improvement in performance.

Option "B" would be to source a good EGR someone has removed in the classified sections or LS1 specific boards such as LS1 tech... You can probably score one for either cheap or free from numerous folks who have eliminated theirs.

It's on the passenger side in the front of the cylinder head, and has a tube leading into the intake throat directly behind the inlet. You can have it removed in less than 5 minutes and 12 ounces of your favorite tasty pilsner beverage.

Here's the diagram, it's #12 in the pic.

ss ZHO · 06-22-2010, 10:50 PM

Wow. I can not thank you enough!! Great advice and awesome photo.

I read that it was in rear of engine. I was about to put the car up on a hoist to try and find it. You saved me lots of headache.

Thanks x 10

02 WS6 TA · 06-23-2010, 07:33 AM

Anytime.

On the rear of the manifold you'll find the MAP sensor, and that's not so much fun to access with the tranny installed for sure.

ss873 · 07-26-2010, 09:31 PM

I had mine go on my 97 ss. It was an LT-1 though. One knuckle head said it was from my Borla exhaust and it had to be removed. Probrably would have hawked it afterwards the tear off. My mechanic scanned and fixed it for dirt cheap.

07-26-2010, 09:31 PM	#5
ss873 diSSturbed Drives: 1997 camaro SS 30th anniversary Join Date: May 2010 Location: Bethlehem, PA Posts: 23	I had mine go on my 97 ss. It was an LT-1 though. One knuckle head said it was from my Borla exhaust and it had to be removed. Probrably would have hawked it afterwards the tear off. My mechanic scanned and fixed it for dirt cheap. __________________ 1997 camaro SS 30th anniv. SS build # 2461 30th #0873 arctic white/hugger orange LT-1 V8, M6, T-tops SLP strut tower brace/ sub frame connectors CAGS skip shift eliminator Borla cat back exhaust

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06-22-2010, 04:44 PM	#1
ss ZHO Drives: 2011 Mustang GT (formally 1999 Z28) Join Date: Apr 2010 Location: Detroit, Michigan Posts: 60	EGR Valve Replacement - Help Appreciated I have been living with my check engine light for too long in my 1999 Z28 (LS1). I never noticed an issue with performance, but its just annoying. Time to fix it. OBD codes are: P0405 - EGR system fault - ECM detected the EGR position sensor voltage was too low. P1404 - EGR valve stuck open condition - While monitoring the EGR valve pintle position the ECM detected the closed position sensor voltage higher than the learned closed position voltage. The probable cause that both codes have in common is a failed EGR valve. So at this point, I am thinking of replacing the valve (I may try cleaning the existing one first). My questions are: How hard is it to replace EGR valve? Anyone have directions? (I heard its on the back of the intake manifold, but that area is buried in the engine bay, and I don't see how I can reach it). Anyone else have these codes or a similar problem? What was the fix? Thanks in advance.

06-22-2010, 04:57 PM	#2
02 WS6 TA Account Suspended Drives: GM Stuff Join Date: Sep 2009 Location: Panama City Beach, FL Posts: 727	Couple suggestions... If it were me (and it is, as I have three '00 LS1s which I have gone this route with) I'd simply remove the EGR entirely, plug the hole in the manifold (or upgrade to an LS6 or FAST) and have the reporting for the EGR circuit turned off in the PCM via HP Tuners or similar. You'll still skate thru smog, and see a slight improvement in performance. Option "B" would be to source a good EGR someone has removed in the classified sections or LS1 specific boards such as LS1 tech... You can probably score one for either cheap or free from numerous folks who have eliminated theirs. It's on the passenger side in the front of the cylinder head, and has a tube leading into the intake throat directly behind the inlet. You can have it removed in less than 5 minutes and 12 ounces of your favorite tasty pilsner beverage. Here's the diagram, it's #12 in the pic.

06-22-2010, 10:50 PM	#3
ss ZHO Drives: 2011 Mustang GT (formally 1999 Z28) Join Date: Apr 2010 Location: Detroit, Michigan Posts: 60	Wow. I can not thank you enough!! Great advice and awesome photo. I read that it was in rear of engine. I was about to put the car up on a hoist to try and find it. You saved me lots of headache. Thanks x 10

06-23-2010, 07:33 AM	#4
02 WS6 TA Account Suspended Drives: GM Stuff Join Date: Sep 2009 Location: Panama City Beach, FL Posts: 727	Anytime. On the rear of the manifold you'll find the MAP sensor, and that's not so much fun to access with the tranny installed for sure.