ANYONE WITH 90-91 PREVIOUS EGR PROBLEM
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From: sharpsburg GA
ANYONE WITH 90-91 PREVIOUS EGR PROBLEM
Im stumped. After getting a code 32 ( egr) I have checked every vacume line with a vacume pump, changed the egr valve, solinoid and o2 sensor. Also I have run the car at idle with a scanner & checked all the sensors. What else is left and why is this light only comming on in cruise. Has anyone ever had this problem before? This is going to drive me nuts and removing the code from the computor is not going to make me feel any better. Im thinking about giving out a reward to the person who can leed me to culprit.
THANKS FOR ANY & ALL HELP
THANKS FOR ANY & ALL HELP
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Re: ANYONE WITH 90-91 PREVIOUS EGR PROBLEM (bdtenore)
Is your exhaust system stock?
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From: Windermere FL
Re: ANYONE WITH 90-91 PREVIOUS EGR PROBLEM (bdtenore)
I'm not sure if you had this information already, but 90-91 are very sensitive to the dreaded code 32. Common areas to look at are:
1. If your cats are gutted, then you might get the code
2. The vacuum lines that run into the EGR switch are frail and can crack or melt and have a habit of leaking from the fittings (or coming completely off) where they go into the EGR switch. (You said you checked this already)
3. The code is set based on O2 sensor feedback. (you said you already replaced it)
4. If the O2 sensor has been previously relocated (for example, because headers were installed) a heated O2 sensor may be needed since it may not be getting hot enough.
5. The EGR valve is defective (you already replaced)
6. Not enough back pressure do to exhaust system changes.
7. The EGR plumbing is clogged by gaskets. If you have the wrong gaskets on the runners it could plug the hole where the gas is let into the plenum.
You can have a chip programmed to ignore the code.
[Modified by Flame Red, 5:21 PM 4/4/2002]
1. If your cats are gutted, then you might get the code
2. The vacuum lines that run into the EGR switch are frail and can crack or melt and have a habit of leaking from the fittings (or coming completely off) where they go into the EGR switch. (You said you checked this already)
3. The code is set based on O2 sensor feedback. (you said you already replaced it)
4. If the O2 sensor has been previously relocated (for example, because headers were installed) a heated O2 sensor may be needed since it may not be getting hot enough.
5. The EGR valve is defective (you already replaced)
6. Not enough back pressure do to exhaust system changes.
7. The EGR plumbing is clogged by gaskets. If you have the wrong gaskets on the runners it could plug the hole where the gas is let into the plenum.
You can have a chip programmed to ignore the code.
[Modified by Flame Red, 5:21 PM 4/4/2002]
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Re: ANYONE WITH 90-91 PREVIOUS EGR PROBLEM (bdtenore)
If you know the EGR solenoid and motor are functioning properly and the SES comes on at cruise after a few minutes then it's the EGR temp. sw. It's likely not getting enough exhaust gas flow to get it up to temp to close this sw.
You might consider wiring the EGR On command from the ECM back to the temp. sw so the ECM sees the EGR come On immediately when commanded.
If your setup is the same as my '88 the ECM pulls the line to the EGR servo to ground to commnad the EGR On and the EGR temp. sw pulls the line low to signal the ECM that EGR is On. If so with your setup, just jumper a wire from the command line to the servo back to the sensor wire and run the test (Check voltage levels first though).
If this works you can permanently wire in the jumper and keep the ECM happy.
You might consider wiring the EGR On command from the ECM back to the temp. sw so the ECM sees the EGR come On immediately when commanded.
If your setup is the same as my '88 the ECM pulls the line to the EGR servo to ground to commnad the EGR On and the EGR temp. sw pulls the line low to signal the ECM that EGR is On. If so with your setup, just jumper a wire from the command line to the servo back to the sensor wire and run the test (Check voltage levels first though).
If this works you can permanently wire in the jumper and keep the ECM happy.
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From: sharpsburg GA
Re: ANYONE WITH 90-91 PREVIOUS EGR PROBLEM (Marcho Polo)
I just bought the car about a month ago or so and I as not to sure about the exhaust system. I took a better look and what i found is a system with no pre cats and the strangest looking converters ( if thats even what they are) . Has anyone ever seen a converter that looks to be about 10 in diameter and about2.5 ft long. I suppose this could be my problem. So what are my options?
Change the exhaust and go back original or get the chip deal done?
Change the exhaust and go back original or get the chip deal done?
Burning Brakes
Joined: May 2001
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From: Kentucky
Re: ANYONE WITH 90-91 PREVIOUS EGR PROBLEM (65Z01)
You said your car ran fine at idle and produced no code; however when in the cruise mode code 32 popped up. Since the cruise control is vacuum operated could it be you have enough vacuum when running without cruise control and when you engage the cruise control it pulls enough vacuum out of the system to cause you to get a code32 reading? Check the hoses that supply vacuum to the cruise control unit and see what you find, just my 2 cents!
Bill
PS: Might want to check your vacuum reservor also. :) :)
Bill
PS: Might want to check your vacuum reservor also. :) :)
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From: And on the fifth day, subpoenas were served to Obama senior staff
Re: ANYONE WITH 90-91 PREVIOUS EGR PROBLEM (bdtenore)
I believe (don't have the manual for a speed density L98) that it uses the MAP sensor and perhaps the O2 sensor to determine if the EGR has opened when commanded.
However the speed density L98 uses a different EGR valve. The 89 is a negative back-pressure EGR and the 90 is something else. If you do a search you will find a post by David F regarding an experiment he did using the EGR from an 89 in a speed density L98. Not sure I have seen how that worked out.
Another possibility is to use a generic aftermarket EGR that is adjustable. I have not tried one of these and hear it is a real pain to setup correctly.
Another choice is to have a chip burned to shut off the code. You may have enough EGR to pass emissions, but who knows.
Good Luck,
Pete
However the speed density L98 uses a different EGR valve. The 89 is a negative back-pressure EGR and the 90 is something else. If you do a search you will find a post by David F regarding an experiment he did using the EGR from an 89 in a speed density L98. Not sure I have seen how that worked out.
Another possibility is to use a generic aftermarket EGR that is adjustable. I have not tried one of these and hear it is a real pain to setup correctly.
Another choice is to have a chip burned to shut off the code. You may have enough EGR to pass emissions, but who knows.
Good Luck,
Pete
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From: Fort Worth Texas
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Re: ANYONE WITH 90-91 PREVIOUS EGR PROBLEM (bdtenore)
I just bought the car about a month ago or so and I as not to sure about the exhaust system. I took a better look and what i found is a system with no pre cats and the strangest looking converters ( if thats even what they are) . Has anyone ever seen a converter that looks to be about 10 in diameter and about2.5 ft long. I suppose this could be my problem. So what are my options?
Change the exhaust and go back original or get the chip deal done?
Change the exhaust and go back original or get the chip deal done?
Email me if you want me to remove the code in your chip.
cmarcho@hotmail.com
