I get an occasional check engine light, and the computer code says EGR is at fault. This usually happens when on the interstate or a long trip. The check engine light will eventually go out on its own while I am driving, and cycling the ignition on/off will also turn out the light.

I have ignored until now, but I have read on this forum that a bad EGR can be a performance killer if indeed it is faulty. My question is -- how long is an EGR usually good for, and if it were faulty wouldn't the check engine light stay illuminated continuously?

 

You are inferring information not being sent. The code indicates a problem received by the ECM related to the EGR operation. The code does NOT tell you that there is a problem with the EGR valve. Don't shoot the messenger. Pull out your FSM and follow the trouble shooing charts for the code (32?) indicated and correct the REAL cause of the problem rather than just throwing money at it.

RACE ON!!!

 

Hmmm...I have the original GM manuals, not the Helms. It says that the diagnosis of the EGR system which you are referring to does not apply if Code 32 is set.

Do you think this is a misprint? Or maybe code 32 means that the EGR valve needs to be replaced?

Thanks!

 

Code 32

A DTC 32 indicates a fault in the EGR system. It sets when vehicle speed is above 32 mph and engine parameters (i.e., INT, BLM, MAP, TPS) are at a specific value, then the ECM commands an off EGR signal for 2.5 seconds while observing the Intergator change. If INT doesn’t change by at least nine counts for the 2.5 seconds, a Code 32 sets. Also, anytime the actual EGR pintle position and desired EGR position is greater than 3% for two seconds, the code will set.

 

First, the "original GM manuals" are contracted out to Helm Inc. for printing. The FSM and the Helms are one in the same. What I said was, "follow the trouble shooing charts for the code (32?) indicated". The manual says not to follow the trouble shooting chart for a code 32, when diagnosing a code 32??? THAT doesn't make sense. If a code 32 meant to replace the EGR valve in the case of a code 32, it would say so in the chart you say the FSM says not to follow for a code 32. ???



This post makes much more sense than the last (above). Here you have cited what the FSM lists as the cause(s) of a code 32. Notice that it doesn't say it is caused by a failed EGR valve. When the ECM is looking for an integrator change, it is looking for the A/F mixture to go lean, because air (exhaust gases) without fuel has been introduced. This is a normal consequence of the EGR valve opening. With no integrator change, chances are the EGR valve didn't open. Now, the question is WHY didn't it open? Is the valve defective? Possibly, but in most cases, no. Did the EGR solenoid get the signal (wiring OK?) to send vacuum to the EGR valve? Does the EGR solenoid work? Does the solenoid have vacuum available to it? As you can see, there is more than one cause of a code (32 and others) than simply the name of the system that had the malfunction. Based in the last sentence of your last post, you have an EGR position sensor. I wasn't aware that any C4s had these. A lack of pintle movement would have all the same causes as the integrator not changing, bit it males sense to confirm that the EGR position sensor is working properly, also.

RACE ON!!!

 

when I had an intermittent 32 it turned out to be the EGR switch.

 

Mine turned out to be a rotted-away EGR valve diaphragm.

 

Is the ERG switch also called an EGR Solenoid Valve? I have an 85 L98.