How's it going everyone? I have a 1986 K5 4x4 Chevy Blazer w/ 305 engine. Just last week my buddy and I put in a brand new rebuilt Rochester Quadrajet carb. Today we were working on it to set the idle speed and timing on it. We got it to where it needed to be and took it out for a test drive around the block. The test drive went fine. We then decided to go out and grab dinner and we took the truck. While I was driving down the street I noticed the truck to jerk a tiny bit when I would accelerate. I then proceeded to turn on to the main road and about a minute down the road the engine started to cut out like it was running out of gas, but then would start back up then cut back out and so on. We pulled over to inspect things and all seemed fine. We even drove it around in the parking lot and it was fine then as well. I got back on to the main road and about a minute or so down the road it started doing the same thing all over again. This time I took my foot off the accelerator and then re-applied it after the speed decreased and it would run smooth.

Any help would be greatly appreciated. If anyone has any questions please feel free to ask.

 

It sure sounds like the float level is not correct. Either that or the choke is not pulling off.

 

something stupid you can try, try losening your gas cap. my fullsize was a diesel and doesnt vent properly after putting a gas engine in it and was doing that crap to me

 

Yep, definitely a possibility and one quite often overlooked (hey, I did it).