A 1986 could be TBI ( throttle body injection), which uses a MAP sensor not a MAF, or it could in fact be carbureted. One of the things that we used to run into with these early computer controlled cars, especially the carbureted ones was that there was no use of long term fuel trims when the engine was cold. It was common that we would see a rough running engine that cleaned up once the system allowed closed loop operation and the computer could then start correcting for fuel control issues. To give much advice at all we are going to need to know the engine size, and what type of fuel system that it has. (Carb or TBI)
It is a 1986 c10 pickup with a 350 engine Holley 4 barrel carb .still has distributor and rotor and capacitor. I found electric choke wire connector bad . I will have to replace it, but with wire connected it idles better but still missing. I've checked and replaced all 8 plugs. The porcelain was a nice tan color (like it should be )on all 8 of them
According to Mitchell, that truck was originally built with a Rochester M4ME or Rochester E4ME 4bbl carb depending on its origin/destination/emissions level.
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