'94 Chevy 4.3 V6 Misses when AC is turned on

[Texas Jim]

1994 Chevy 4.3 V6 has a strange problem

Runs great till you turn the AC on...then it has a slight miss.
Turn the AC off, the miss goes away.
Grounds under the hood have been checked, but I may have missed something.
It has new plugs and wires... that didn't help any.

Anyone ever have this problem or have any ides on what to check???

 

[OldCracker29]

1994 Chevy 4.3 V6 has a strange problem

Runs great till you turn the AC on...then it has a slight miss.
Turn the AC off, the miss goes away.
Grounds under the hood have been checked, but I may have missed something.
It has new plugs and wires... that didn't help any.

Anyone ever have this problem or have any ides on what to check???

I don't have an answer for you, but I had a '90 Buick Century do the same thing.

 

[ScottyBoy]

Could be that the AC compressor is on its way out. If its starting to bog down and/or randomly locking up, that will put extra stress on the motor causing it to bog down and seem like its missing. When the compressor on my truck started going out, that's pretty much what it was doing. It didn't exactly seem like the engine was missing, but it started randomly locking up and putting extreme tension and stress on the AC belt causing it to flail around wildly. I am pretty sure the 4.3 only has one belt, no seperate belt for the AC.
Try looking at the belt with the engine running. Then have a helper inside the truck turn on the AC. If the belt begins to jump/flail around with the AC on, then that would REALLY have me believe the compressor is going out. And try checking it at both idle, and at around 2000rpms . Mine was far worse at higher rpms.