Stumble rough idle

RegalRon5243

New Member
Joined
Dec 6, 2015
I recently bought a 85 hot air and I'm trying to get it back running. I'm new to the GN's so excuse the dumb questions. I have done a lot of research and have used this forum thoroughly. The problem I have is the car idles rough and will not accelerate without hesitation. I have adjusted iac, tps, fixed a couple vacum leaks. I do have a trouble code (23)for ats which I don't have, the car has a 87 ecm though, would this cause issues running?
 
I cleaned the maf, didn't make a difference. I think I have a bad coil pack or something else causing not all cylinders to fire. I unplugged the #6 plug wire from the coil and the car runs no different than when it's connected. Checked all the wires they look good and are connected, pulled the plugs, #4,#6 look a lot cleaner than the rest but none looked bad. Any thoughts or suggestions is appreciated.
 
First I would check the firing order, if its right, then would run a compression test on #6.
 
I cleaned the maf, didn't make a difference. I think I have a bad coil pack or something else causing not all cylinders to fire. I unplugged the #6 plug wire from the coil and the car runs no different than when it's connected. Checked all the wires they look good and are connected, pulled the plugs, #4,#6 look a lot cleaner than the rest but none looked bad. Any thoughts or suggestions is appreciated.
Check the injector harness. Also check the harness weather pac plugs both sides. Casper has new injector harness and plug and connectors. John
 
Also you can hook up a timing light to each sparkplug wire and see if that cylinder is getting spark. Just to rule it out
 
Well it's been a while since I've had a chance to work on the car but I finally have it running. It had/has multiple issues, but I think the biggest was the rockers being out of adjustment. One of them pulled the stud out on the passenger side head, had to pull head put a helicoil in, another was loose nut fell off. I also changed MAF sensor, new plugs, and wires. Car idles good runs ok but now I have no boost. Going to double check all vacum lines today. ..thanks again for all the help.
 
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