aliecks

Alright, I got it adjusted and the first start up after plugging the ISA back in the truck , it sat at about 2000RPMs. I plan to take the ISA apart and see if I can figure anything out. To go back a little bit, I replaced my EGR gasket after a smoke test and seeing smoke escape from there, also while tightening that down I noticed I was missing the rear lowest manifold bolt/stud. Threw a bolt in there and after all of that the stumble/stutter seemed to go away and has been gone. I’m assuming I’m good on vacuum leaks but I’ll smoke test it again when I remove the ISA to verify. I’ve been smoke testing through the brake booster vacuum, if anyone has other places to test let me know!

I’ll try this adjustment procedure, drive it home and report back later today or tomorrow with how it’s acting. Thanks

Alright, long story short I got a short bed 2.5L Comanche from my grandpa, he treated it well but he hasn’t drove it much the past few to more than few years.(Other than to deer camp and back once a year) So I’ve have it for a few months and I’ve decided to go for a Street Comanche clone type of deal with the help of ORG parts. Before I get too crazy with cosmetics I’ve been chasing a “stumbling idle” and/or high idle issue. I’ve scanned the forms and watched plenty of Nickintimes plus other creators. I have a Snap-on MT2500 and with my “expertise” lol I diagnosed the TPS being bad. I replaced it, set it to 4.64-4.65v at WOT, I replaced the EGR valve gasket and verified my ISA is functioning. Test drove it yesterday about 10-15 minutes and the truck did well. After getting to operating temp it was sitting at about 1000-1100RPMs with A/C off. Today I drove the truck home about 25-30 minutes county roads, again after operating temp at idle I would be sitting at 1000-1100RPMs. My stumbling idle issue is gone I’m assuming the EGRR gasket leak and the faulty TPS was causing that. I think my ISA is out of adjustment from previous mechanics messing with it causing my high idle. MY FINAL QUESTION: What is the actual procedure for adjusting the ISA on a 89? In my Chiltons manual it says the 89-90 doesn’t have idle speed adjustments and is controlled via computer…so is that right or do I go the unplugged ISA 3500RPM route? Or am I completely wrong? Anyways thank you for coming to my TED talk.