89 Club Wagon rough idle\stall after EGR sensor install
 

Hello all, hoping I can get some ideas for a fix here. I have a 89 Club Wagon 5.8l that has been great for the years I've owned it but the CEL has been on. I pulled codes a few years ago because of a idle problem and the two I got pointed to the IAC and the EVP. I replaced the IAC which fixed the idle issue. About a week ago I replaced the sensor atop the EGR. Van ran great on the test drive until I pulled into the parking lot where it stalled out. Did some checking and found the EGR bolts were a little loose. Tightened them and it drove home fine but the problem has resurfaced. When I come to a stop or even just parked but usually after van is warm it doesn't want to idle. It won't start unless I barely give it throttle and if I let off the gas it sputters and sounds like its running at 200RPM then it will die. It runs great off idle. I tested the EGR and it seems fine. Timing was fine. What about replacing the sensor would cause this issue? I noticed the EGR tube on the exhaust manifold moves around quite a bit but it's still attached. Any ideas would be very much appreciated and thank you in advance. Mike

It's all about the Codes, but sounds like a Vacuum leak or a dirty Intake/ Throttle Plate..........

Thanks for the reply. CEL is not lit but I will check it for anything stored in the next hour or so. I pulled throttle body and cleaned it and replaced TP sensor. There was a nice coating of gunk looking down into the intake but it didn't appear excessive....whatever that means. I did do some spraying around various vacuum lines looking for leaks but definitely wasn't thorough. I will finish the inspection today. Any additional ideas or suggestions would be very much appreciated, thank you.

I was thinking since the EGR bolts were loose,(or you had it off) the Intake Gaskets were shrinking with age and there might be an Intake leak. Also all that (gunk) plugs up the EGR ports and there is a little screen in the EGR Gasket itself too. It's just time for that major clean/tune up and a lot of new rubber Hoses............

Appreciate the info. I did take the EGR off to verify it was ok at the time I replaced the EVP. I didn't notice the screen on the EGR gasket. I'm pretty sure there wasn't one. As for the vac lines that wouldn't be a bad idea.
I did do a KOEO and KOER test and, although CEL was off, got some codes. KOEO returned code 34 which, according to Chiltons, is EVP voltage above closed limit. With engine running I got these codes: 22(2 definitions) BP sensor out of self-test range and/or BP sensor or MAP out of range, code 42 HEGO sensor circuit indicates system rich and again code 34.
Code 34 was one of the codes I got some time back and, after replacing EVP, turned CEL off. Not sure what's going on there. So after seeing these results would your top reason for these symptoms be a intake leak? Thank you for your time and any response/suggestions are appreciated.

Just a guess from here, but with Codes 34-22-42 all saying out of range there's a bigger issue going on. It could be Intake Gaskets leaking and throwing them off, but you'll need to spray around the Intake with (something) and listen for changes in Idle RPMs. That Code 34 will come up for plugged EGR passages at high millage (gunk)........

Hey I really appreciate the info. The van does have close to 150k miles but unfortunately I need it this summer for hauling firewood for the winter. No biggie. Thanks again. Can anybody add to what econolinemanor has suggested? All opinions and insight welcome, thanks.