Strange problem
 

when is tart my car i have to let it warm up before i can drive it but once its warmed up and i turn it off the restart it itll start acting up. it wont rev higher than 3000rpm and stumbles and backfires under that. this started happening once it started to get cold out but im not sure whats wrong. ive changed the dist cap/rotor, wires and plugs. it helped a little but that not much. I have a 1983 turbo

Sounds like another AFM problem. Read the sticky thread in Performance?technical about rebuiling your AFM.


https://www.zdriver.com/forum/showthread.php?t=15277

Rod.

I'd go with that or maybe a faulty head temp sensor.

just unbolt your AFM and with a butter knife slowly pry off the black box on your AFM use a type of non oilly cleaner to clean out your AFM .. i think eletrical spray will work.? any other hints yall ?

had the exact same problem, changed my oil and put only synthetic in, 5w30 and runs better than ever, also changed my valve cover gasket

well changing oil dose a lot for an international (power stroke) but I don't know what it could do for a runing rugh or rich problem on this gas powerd nissan.
let me ask when it pops and farts and all this stuff, are you putting out black smoke, and smelling gas, or partially burned gass?

Also maybe check injectors, and compression test, check timing. I don't know if these old motors can even jump timing.

you will usally finde that timming problem to be with a broken or loose bolt on the distributor housing.

Vacuum Leaks! change all the hoses one at a time. Cold start and restart problems were solved on my car with a new fuel pump, I dunno why, the pressure test was good, it ran good, but with a new pump its so much better. check the intake boots out, and have the starting-charging systems checked out, mainly output test on the alt, and load test on the batt, also check for bad grounds, after all this if it stil doesnt run like a champ, recheck the cap-rotor. cheap ignition parts will cause you nothing but problems.