e30_eric

I replaced the coolant temp sensor today as well as changing the spark plugs, she is running at her best now. Thank you to everyone who helped with the diagnoses

If so i checked that with a multimeter and it checked out

Your talking about the manifold air temp sensor correct?

ok so the O2 sensor came in today and i replaced the old one, she is still backfiring and misfiring and generally running terrible up until 180*F once she reaches 180* she smooths out and drives great, so the O2 sensor definitely was the fix at operating temperature. I'm thinking to fix the startup will be done by replacing the coolant temp sensor to help fix the cold enrichment then she should run like new. Thank you guys for all your help!

ok so after a little looking, the manifold bolts are there and are tight, they look relatively new so I'm thinking the po replaced them at one point. The O2 sensor looks extremely old, maybe the original one that came on the truck, so i am going to order one of those and see where that takes me. I attempted to test it using the outline you provided for the 4.0 but the wires are different colors so i assume its not the same senor as for the 4.0's

yeh i just did some quick searching around the forum and found a older post from you outlining the test procedures for the 4.0 i will try it and see what i come up with

Cruiser before i made this post i went through your tips and re did and cleaned all my ground connections with no improvement. Your tips are awesome though! Jeepdriver i thought about the O2 sensor, is there anyway to test it before i replace it?

Thank you, yeh i agree i would rather test everything possible before throwing parts at the problem. I would still like to know if the cts could be the culprit

ok i will check tomorrow in the daylight. if they do happen to be broken do you know what size and thread pitch they are so i can replace them?

ok then 88 it is, i have not checked to see in the intake manifold bolts are tight but i know they are there. Do those bolts have a tendency to back themselves out? I ask because the truck has been running great for a few months now and just recently started this misfiring/backfiring problem. I will check the bolts tomorrow morning just in case. by the way thank you everyone for the input so far

this is her

it is a 86 i believe, it was titled as a 88 but from what i can tell from the paperwork its really a 86. I did do a fuel pressure test and it tested at 15psi which from what i have read that is perfect, i also did a egr delete in case it was stuck open and that did not fix the problem either. I'm wondering if it is the coolant temp sensor, from what i have read that tells the ecu to adjust ignition timing according to temperature

Hey guys, I have a 2.5l tbi 5 speed Comanche that is misfiring and running lean. The components I have already replaced, include, map sensor, plugs, wires, distributor cap, and rotor. I have tried two different ignition coils. I have checked the voltage differential in the tps sensor and it is within range, I tested the ohm differential across the Mass Air Temp sensor and it was 1000ohms which from what i have read is spec. Yet when i pull the plugs they are dry and nasty which leads me to believe that is running lean. I'm at a loss as to where to go from here, any help would be much appreciated.