22R stutter/cutting out

[valon5150]

84 22r. it has been stuttering under load at various speeds. it's not consistent at all, sometimes it will be a little one and other times the truck falls straight on it's face and feels like it's bucking unless i let off the gas immediately, then i can re accelerate and it's fine. this is the first vehicle i've owned with a carb so i really don't know anything about them. It seams to me like a fuel issue, so first and easiest thing i have done was replace fuel filter, didnt change a thing.

Hoping some of you guys might be able to point me in the right direction, my next guess would be fuel pump is cutting out, but since i don't know anything about carbs i was wondering if it could be something with that before i go and get a new pump.

Truck has relatively new dist. cap, wires and plugs. about 20k since they were all replaced.

Thanks for any advice

[HogCanyonHopper]

Have you had the carb apart for a good cleaning? Could be some junk in there causing issues. A good cleaning can help carb problems alot. Also, I think its called the accelerator pump??? maybe check that. I rebuilt the 20R in my 80 and could never get it to run right. I think the problem was the carb, but the motor didn't stay in the truck long enough to find out. I went with a 3RZ swap. Carbs can be a real PITA. Good luck 

[valon5150]

checked the Auxiliary accelerator pump vaccum line and it didnt look like it was getting any fuel leaked into it. Blasted the carb out with carb cleaner. will find out tomorrow morning if it helped any.

[valon5150]

well didnt help any, ran to the hardware store and it was still acting up. likes to do it in the high rpms in 1st and 2nd and then if i'm in a higher gear accelerating hard it's fine unless i let off to just maintain speed.

guess i should pull the carb apart and clean it real well like ya said HogCanyon. Don't think i'll have time until later in the week though

[Nation]

I had a similair issue. Same symptoms. Oonly after a good 20-30 min drive tho and mostly up hill. I replaced the filter, fuel pump, and go over your vacuum lines.  Anyway after i replaced those items i havent had that issue. Hope its that easy....

[Nation]

Also if yoi still have the aisin carb, it may have an internal fuel filter