Acceleration Woes

As the title states, I'm having accleration woes in the jeep with my AMC 360.

While cruising around in the jeep and under acceleration, once the rpms rise to 2k+ it seems to "lurch" forward as if stalling out while speeding up. Interestingly, I can sit in my drive way and rev the jeep up and it runs perfectly. This leads me to believe it's more than likely a drive train issue. Any thoughts on the culprit?

 

Don't let the driveway test fool you. When an engine is under load (accelerating) it behaves completely different then when it is sitting still and being revved. Sounds like a carb issue, maybe a accel pump?? Typically drivetrain issues like you describe only happen once or twice before you hear awful noises and something BIG breaks. I would look at the carb and go from there unless the drivetrain IS making noises.

 

Just a suggestion, check plug and plug wires. A cylinder not firing is a lot more noticable driving then still. Could be a wire that is shorting or distributor not firing @ all points. Can come and go.

 

I've checked the plugs, they all look good and clean. Not sure on how to check the wire condition, however. I've checked the distributor cap, and it's on tight and firm, although I might have messed something up when I hooked up my tachometer, but I doubt it as it occured before I hooked it up.

The carb should be okay, its a brand new edelbrock with under 200 miles on it. Could be the fuel pump or fuel related as it feels like the engine stalls when under acceleration, but I'd think this would be noticeable when reving in the drive way.

 

Defintly sounds like a carb problem. Its a four bbl right? It might be a problem with the secondarys then. The secondarys might not open when you rev it , but will when you drive it.

 

Yes it's a 4 BBL mated to an edelbrock manifold. I guess I'll have to step outside in a few and take a look at the carb. I didn't install it myself, so I figured it should be on the up and up.

Unfortunately I have zero clue on adjusting carbs. I've searched the site for some info but didn't come up with anything. So when I pull the air filter off, what should I be looking for?

I appreciate all the help by the way fellas.

 

Did you check the inside of distro for carbon tracking? Or maybe hairline crack? I had a (non-Jeep) rig that did the same thing, and found a carbon track that allowed the spark to jump when accelerating, but idled and revved fine. Just a thought.
Mike

 

My blue jeep i picturedin here did the samething...the problem was a pinched fuel line going from the fuel tank to the fuel pump....i changed out the bad fuel line and now she will purrrrrrrrrrrrrrrr on down the road

 

Finally got it pinpointed. Took it to a mechanic buddy of mine and figured out it was the distributor. The inside of the distributor was in pretty bad shape. Swapped it out for another one, adjusted the carb a bit, and the amc 360 pursR)

Thanks for all the input fellas!