Super high idle while in neutral

[DropThatHammer]

Just recently my 87' 2 liter Mighty Max started to idle really high while in neutral. I'm going to check timing this weekend, but before then i'm looking at probable problems causing this issue. I've adjusted the carburetor in every way possible and all it will do is bring the idle up even more from its already ridiculously high idle but i't won/t bring idle down to a normal speed. I've checked for vacuum leaks and can't seem to find any. Anyone ever have this problem?

[pennyman1]

vacuum leak - may be carb loose on manifold, or the hoses going to the box on the drivers fender under the hood. Or the seals went in the carb and its dumping raw gas into the carb....

[DropThatHammer]

vacuum leak - may be carb loose on manifold, or the hoses going to the box on the drivers fender under the hood. Or the seals went in the carb and its dumping raw gas into the carb....

I'll recheck all vacuum lines. It starts up and does cold idle fine, but after cold idle the idle starts to climb and stay high if that helps..

[camoit]

does it have AC

[DropThatHammer]

does it have AC
No AC and not heater for that matter >:l last owner decided to remove the heater core hoses.

[mighty]

Anything ever come of this? I think I am having the same issue.

[noahwins]

I had a similar issue on my new to me '90 (fuel injection not carb so not sure if this applies). The screw was backed all the way out so it wasn't touching and it was still idling at ~1050. I loosened the 12mm nut on the throttle plate and clocked it towards the intake as much as possible so it would stall when warmed up. Then I was able to use the screw to adjust idle normally. The throttle cable was fine but over years the nut and lock washer on the plate had backed out. HTH

[Jorge83]

Mine idled too high and was on the failed emissions test then it was brought down and they say it's too low of idle. Was told a possible vacuum leak, any solutions?

[Ramshorn]

Any luck DropThatHammer? I had the same problem and replaced the carb with the weber 32/36 - problem solved! I'm pretty sure the seals went in the factory carb and it was pouring gas into the carb (like Pennyman said above). Truck runs great now! Keep us posted.