engine surges at idle
Amateur
Joined: Nov 2012
Posts: 38
Likes: 0
You know what's funny is my 92 is doing the same thing and has been for awhile and I was just about to post the same exact question. I can't for the life of me seem to figure it out.
I thought I had it nailed when I recently found oil inside the distributor covering the pickup coil in a thick film and chunks of rubber. One nice new distributor assembly later, it's still idling like crap. The truck was actually stalling at one point when the map sensor went bad, but now, it's just more of an annoyance than anything else.
Not trying to hijack this thread, but here's my list in case you find something you might have missed or I missed something you have already checked. All of mine are confirmed functioning or replaced and good functioning parts, not just a guess and check method as well. Let's figure this out for both our trucks sake!!!
1.) The infamous factory splices and grounds. There's way more than 1 or 2 once you start pulling the harness apart too, so make sure you got em all.
2.) IAC, TPS, MAP sensors. All good and working right.
3.) Throttle body thoroughly cleaned w/new gasket, all the intake vacuum ports completely cleaned, and vacuum connections checked/replaced.
4.) Distributor assembly replaced with new pickup coil b/c of oil seal leak.
5.) 2 good working ECM's one has been running for 750 miles and one good spare on the passenger floor.
6.) Ignition switch replaced b/c of internal short
7.) New CPS, PCV valve and gas cap replaced because they all looked worn. (I'll admit this one was also a little out of desperation too)
8.) New fuel pump in tank b/c it left me on the side of the road. (always fun) Tested, confirmed bad and replaced.
9.) 2 good working ignition coils replaced and connection zip tied in place for peace of mind
10.) Catalytic converter hollowed out, and emissions lines all capped with new exhaust install.
11.) New cap, rotor, plugs, and wires about 6 months before the new dizzy.
12.) ALL electrical connections have been triple checked, cleaned, air dried, and coated with dielectric grease.
The only 2 things I got left that even come to mind is the fuel pressure regulator on the rail because it appears to be original and I never checked it after the fuel pump replacement, and coincidentally my ECM is also not reading from the coolant temp sensor now and not reading at the gauge either. I know how frustrating an issue like this can be, so let's figure this one out for both of us along with some help from the wealth of knowledge on this forum. Cheers guys!!
I thought I had it nailed when I recently found oil inside the distributor covering the pickup coil in a thick film and chunks of rubber. One nice new distributor assembly later, it's still idling like crap. The truck was actually stalling at one point when the map sensor went bad, but now, it's just more of an annoyance than anything else.
Not trying to hijack this thread, but here's my list in case you find something you might have missed or I missed something you have already checked. All of mine are confirmed functioning or replaced and good functioning parts, not just a guess and check method as well. Let's figure this out for both our trucks sake!!!
1.) The infamous factory splices and grounds. There's way more than 1 or 2 once you start pulling the harness apart too, so make sure you got em all.
2.) IAC, TPS, MAP sensors. All good and working right.
3.) Throttle body thoroughly cleaned w/new gasket, all the intake vacuum ports completely cleaned, and vacuum connections checked/replaced.
4.) Distributor assembly replaced with new pickup coil b/c of oil seal leak.
5.) 2 good working ECM's one has been running for 750 miles and one good spare on the passenger floor.
6.) Ignition switch replaced b/c of internal short
7.) New CPS, PCV valve and gas cap replaced because they all looked worn. (I'll admit this one was also a little out of desperation too)
8.) New fuel pump in tank b/c it left me on the side of the road. (always fun) Tested, confirmed bad and replaced.
9.) 2 good working ignition coils replaced and connection zip tied in place for peace of mind
10.) Catalytic converter hollowed out, and emissions lines all capped with new exhaust install.
11.) New cap, rotor, plugs, and wires about 6 months before the new dizzy.
12.) ALL electrical connections have been triple checked, cleaned, air dried, and coated with dielectric grease.
The only 2 things I got left that even come to mind is the fuel pressure regulator on the rail because it appears to be original and I never checked it after the fuel pump replacement, and coincidentally my ECM is also not reading from the coolant temp sensor now and not reading at the gauge either. I know how frustrating an issue like this can be, so let's figure this one out for both of us along with some help from the wealth of knowledge on this forum. Cheers guys!!
