A little history is important.....

I purchased the car in December of 21, and have been fighting the intermittent CEL since. I didn't check for codes when I got home from work yesterday evening, (as I had a pork loin to smoke,) but I'm going to assume it's a Code 32. Yesterday on the trip into work which is 45 miles, (55 minutes,) and mostly @ 60 MPH, @ 8AM with the OAT at about 83 degrees, R12 A/C cooling the car nicely, I didn't get the CEL. Returning home @ 5PM, mostly @ 60 MPH, OAT @ 98 degrees, AC on Max with the fan on II, the CEL illuminated about 15 minutes into the trip, and remained illuminated the entire trip home. No change in performance was noted. When I restarted the car about 30 minutes later to move it into the garage, the CEL was gone. From what I have observed over the term of this problem, the CEL only illuminates when the OAT is hot. A couple of times in the past that it has illuminated, further into the trip it extinguished by itself, but I cannot pinpoint the reason.

In May of 22, I replaced the EGR Solenoid and MAP Sensor. No change.
In November of 23, I replaced the 2 cracked/deteriorated "boots" on the vacuum lines going to the EGR solenoid. No change.

Neither of these services resulted in any change of the CEL's behavior.

I have contemplated removing and replacing the EGR Valve, but I am not one that generally troubleshoots by changing parts until the problem goes away, (besides the fact that it's not the easiest job in the world,) so I would appreciate some help.

Thanks!

 

I think the first thing to do is to check and pull the codes to see what is actually going on.

Even though the light is out, it should store the code in memory as long as the battery is not disconnected.

 

...But only for the previous 50 engine start/run cycles. Retrieve the code(s) before too long.