87-4MULA

Alright so i have been having my SES go off intermittantly reporting a code 32 which is stated as an EGR system malfunction. I find this odd because the only time when the light goes on is when ive been on the highway for more than 10 minutes after doing 70 or so. also i kno the egr is acting up b/c when I start driving the car around cold the engine will bog down to like 500 rpm when at a stop until the car starts to warm up. My question is: has anyone had a problem like this and whats the best way to look at the problem. i.e. is this a possible wiring problem or has the diaphragm in the EGR finally rotted away. Also does anyone kno what i need to do to just put on a TPiS EGR block off plate? Do i need to do anything to the computer if i go that route? personally i dont giv a F*** bout the EPA

fulo

I had a similar problem back on the days when I had the ECM... I had to replace the EGR, and problem solved But before you consider that option, make sur that the wires are fine, that the vacumm hose is in good shape. One thing you migth consider is starting the engine, let is reach operationa temp, and if possile, dis connect ahd plug the vacuum hose. See how it behaves. It could also be the vaccum cut switch that is damange. In theory, the EGR should oly operate under certain conditions, and your described bog down coudl indicate that is not functioning correctly. I jusr read that the EGR normally operates when the car is going between 30 to 70 mph. Check to see if the EGR Realy Vacuum cut swich is in O.K shape.

Kevin91Z

iTrader: (1)

The EGR is the only emissions thing the computer keeps track of, so you cant remove it without a custom chip disabling it in the computer, or you'll still get the SES light.
The diaphragm is probably dirty after 20 years of service. A new valve should fix it.

87-4MULA

well i went out last nite and tested the valve and it did not want to hold vaccuum. so i figured that the valve was bad. i wake up this morning and go play around with it some more. valve holds vaccuum and checks out. then i test the solenoid and that checks out. then i put the valve under vaccuum and start the car and vaccuum drops. so according to the giant service manual everything is 100% OK. Heres. my theory:
there is manifold vaccuum applied to the valve thru the solenoid and the negitive backpressure from the exhaust reacts against spring pressure to activate the vac bleed off valve in the EGR. 20 years of corrosion must have been holding that bleed off spring in place and causing the vavle to not hold vaccuum. My playing with it and adding and subracting more that manifold vaccuum must have freed it up a bit. I m still going to keep an eye on it and see if the problem really is fixed or not now.

Air_Adam

Sounds to me like the EGR is sticking open a bit once it warms up. Late '70s Chrysler V8s were bad for this.

The way its supposed to work, is to be closed at idle and open up as part-throttle RPMs climb (should not be open at WOT). It should be open at highway speeds. If it is sticking in one position, then the computer may not like the position its in on the highway (I can't remember if the computer keeps track of position on these cars, but it does on my LT1 car) and setting the code.

Anyway, the stumbling, low, rough idle does indicate an EGR valve sticking open at least partially.

87-4MULA

well its been a week and everything is good. no lights flashing. And my mileage went up a touch. so, well, you already kno my theory

mw66nova

iTrader: (13)

i'm having this same problem. if i can come up with another 89 lb9 eprom, i'm gonna send it to a buddy to have the EGR disabled and get a block off plate. seems like the best way to fix it. what are the advantages to keeping the EGR?

Air_Adam

EGR can help cruise fuel mileage, and it will run somewhat cleaner with EGR. It helps by letting you have more timing in the engine, and running a bit leaner, without running into pinging problems.

mw66nova

iTrader: (13)

hmm...think that my malfunctioning EGR is why i've got a code 13 as well? (lean o2 at cruise)

Kevin91Z

iTrader: (1)

Could be, but usually a bad EGR will set a code 32. Code 13 would set if the O2 sensor is shorted or grounded, or if you have an excessive exhaust leak letting extra air into the y-pipe before the O2 sensor.

mw66nova

iTrader: (13)

hmm, no exhaust leaks, maybe i should just put a new o2 sensor in it.

87-4MULA

yea i ended up replacing the egr valve and the temp sensor. I still had the light come on when i had it on the highway last week. Its funny, it only happens when im on the highway doing 75 for more than an hour. other than that everything runs perfectly

89camaroRS6

Recently i had to replace my egr it was doing the same thing as described in the first post and it went away but a day later when i am driving for about 15 min doing 50 my ses came on and popped up code 13 bad o2 circuit any ideas on what it could be?

Kevin91Z

iTrader: (1)

Yes, read my post #10 in this thread.