Question about the EGR
Thread Starter
On The Tree
Joined: Sep 2007
Posts: 177
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From: San Antonio, TX
Question about the EGR I was driving my T/A the other day when my SES clicked on. I went to advance and hd them scan it for me and it was P0400...EGR Flow yadda yadda. Car runs fine (no loss in power / response) at idle, partial (where egr would actually foul things up) or WOT.
This is a street car and has 93k miles on it. My question is which is more likely the culprit...EGR Solenoid or EGR Valve.
I am not going to get it fixed in the next few months because I'll be heading out of the country and I don't need to pass emissions until next july. Also cant pull the valve off right now (got one hand in a cast and doing anything is a pain to theses cars with one hand - cant even hold a mirror to see what Im doing).
This is a street car and has 93k miles on it. My question is which is more likely the culprit...EGR Solenoid or EGR Valve.
I am not going to get it fixed in the next few months because I'll be heading out of the country and I don't need to pass emissions until next july. Also cant pull the valve off right now (got one hand in a cast and doing anything is a pain to theses cars with one hand - cant even hold a mirror to see what Im doing).
Thread Starter
On The Tree
Joined: Sep 2007
Posts: 177
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From: San Antonio, TX
I though that unless you had a larger cam that created its own egr effect that removing it would make the car run like crap (retard the timing) at partial throttle. Was I mis-informed?
On The Tree
Joined: Apr 2007
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From: Northvale, NJ
My EGR valve was leaking about 3 months ago - that was the subject of a recall on these cars for some years - apparenly it develops pinholes.
Disconnect the vac line from the valve and put a piece of rubber tubing on it long enough for you to blow into it - if it won't hold pressure you found your problem.
I believe the solenoid throws a different code.
Disconnect the vac line from the valve and put a piece of rubber tubing on it long enough for you to blow into it - if it won't hold pressure you found your problem.
I believe the solenoid throws a different code.
Thread Starter
On The Tree
Joined: Sep 2007
Posts: 177
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From: San Antonio, TX
I appreciate the info...I'll try blowing in it in the next day or two. Now assuming it is bad it seems like I have three options unless I don't understand emissions tests:
1) Get new EGR and / or solenoid installed
2) Get a block off plate and send PCM off to madz28 for tuning and !EGR
3) Leave bad EGR and Solenoid on car and send PCM off to madz28 for tuning and !EGR
Now for my questions...
1) Will leaving a malfunctioning EGR or solenoid on my car hurt it either in reliability or performance (MPG and Power)?
2) If I either go the route of getting blocked or assuming the answer to question #1 is no AND I get the PCM to block the code by a madz28 tune, then will I still pass emissions (NC)? I understand that there are 5 readniess monitors and that I should only need 3 outta 5 working. As long as 3 outta 5 work and the SES light doesnt light up / throw a DTC, that passes (I think this is how emissions work).
1) Get new EGR and / or solenoid installed
2) Get a block off plate and send PCM off to madz28 for tuning and !EGR
3) Leave bad EGR and Solenoid on car and send PCM off to madz28 for tuning and !EGR
Now for my questions...
1) Will leaving a malfunctioning EGR or solenoid on my car hurt it either in reliability or performance (MPG and Power)?
2) If I either go the route of getting blocked or assuming the answer to question #1 is no AND I get the PCM to block the code by a madz28 tune, then will I still pass emissions (NC)? I understand that there are 5 readniess monitors and that I should only need 3 outta 5 working. As long as 3 outta 5 work and the SES light doesnt light up / throw a DTC, that passes (I think this is how emissions work).
Why would you send it to get tuned if you just remove the EGR? There isnt a huge need for that.And EGR removal shouldnt throw a code.Pretty much all it does is let warm exhaust back into the intake manifold.
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Verdad Gallardo Thread Starter
On The Tree
Joined: Sep 2007
Posts: 177
Likes: 0
From: San Antonio, TX
Well the reason I said tuned is because I don't know anyone near me with LT1 edit that could go into my PCM and modify "aka delete" the EGR code to were it would not trigger the SES to come on. Also since he would have the PCM already I would just have him tune it as well. That way even if the EGR still scanned as not ready I would still have 4 of 5 ready monitors to pass inspection AND the SES light wouldnt trigger because of the EGR.
Does this makes sense or am I confused about the emissions test? As I understand it inspection requires no continous SES light with engine running AND 3 of 5 readniess monitors showing ready.
Does this makes sense or am I confused about the emissions test? As I understand it inspection requires no continous SES light with engine running AND 3 of 5 readniess monitors showing ready.
well depending on where you are located and what they use for emissions... egr cools down the combustion chamber temp by eliminating NOx emissions... you can go either route, my valve is stuck closed so i disabled it from the pcm and left it on there. if it is an insufficient egr flow issue, the valve is probably sticking. egr really causes no loss in power on a street level, and does partially help fuel mileage... i would replace it if i were you. this is from a technicians point of view... my main deal is i wouldnt want you to fail emissions testing from deleting it
Back on track tho, worked , its gone, no codes.
Thread Starter
On The Tree
Joined: Sep 2007
Posts: 177
Likes: 0
From: San Antonio, TX
1994 is OBDI correct? Did that have a code for the EGR malfunctioning? I have a OBDII. I know the emissions requirement is different for '96+. If I knew I could pass emissions by just having it deleted so the friggin SES light would turn off, I would just leave mine on it.
If anyone has passed a NC inspection / emissions test with a OBDII LT1 with the !EGR in the PCM and with either a block off plate or a not properly functioning valve on it...feel free to chime in.
I just don't want to waste the money on replacing the valve if I can still pass by just getting deleted.
Finally if I have the EGR disabled with LT1 edit or HP tuners...will it ever come back on unless the PCM gets set back to standard? What I mean to say is how is getting it "deleted" differ from say using a DTC scanner turn off the light (in which case it comes back on 15 miles later)? Does the tuning software set the sensor permenantly to the ready value, regardless of what the sensor actually says?
BTW I might be interested in your valve and/or solenoid if I end up having to replace it.
If anyone has passed a NC inspection / emissions test with a OBDII LT1 with the !EGR in the PCM and with either a block off plate or a not properly functioning valve on it...feel free to chime in.
I just don't want to waste the money on replacing the valve if I can still pass by just getting deleted.
Finally if I have the EGR disabled with LT1 edit or HP tuners...will it ever come back on unless the PCM gets set back to standard? What I mean to say is how is getting it "deleted" differ from say using a DTC scanner turn off the light (in which case it comes back on 15 miles later)? Does the tuning software set the sensor permenantly to the ready value, regardless of what the sensor actually says?
BTW I might be interested in your valve and/or solenoid if I end up having to replace it.
Last edited by jaywalkersw; Oct 5, 2007 at 12:02 AM. Reason: Forgot something
