Here's the scenario, this all started after a day of hard driving (of course).What it does is, runs fine in the garage and under idile, did it to check timing at 36 advanced, ran up tp 3500rpm no prob. but when its up to temp. and I try to drive it, it wants to stall when I step on the gas. It seems like, when I try to give it gas someone is flicking on and off a kill switch.
It actually stopped all togather the other day and standed me. But next day it started fine.
I have now since changed the Coil, Points and the Condenser. Its getting gas no prob. what the hell is it...

350/270hp 4 speed

 

Jake.......Question(s). Does the car have the original Q-Jet on it......and what you are describing. Is it from a dead stop, or, more like if you're already running at some form of speed and give it a "harder" acceleration. (where it stumbles for a sec, almost dead, then goes)?

(I've had that issue on some car in the past, where the accelerator pump material was worn so it wasnt giving the car a squirt and running lean for a second)

(any backfires at all?)


BobR

 

Question(s). Does the car have the original Q-Jet on it
Yes.
If I drive it I can only putt putt allong then when it try to add more rpm it wants to stop runing almost. No large back fires, just wants to quit. But I can put it nuetral and rev it up fine.

 

Have you replaced your fuel filter lately? Stupid things happen with a clogged filter

 

 

change both about a year ago, I'll ck though.

 

This may be obvious, but, did you reconnect your vacuum line after retiming?
TJ

 

I would look for a vacuum leak first

 

it almost sounds like a fuel delivery problem to me...sounds like you get enough fuel to idle it and do a quick rev but under load conditions you don't get enough gas...my buddy had a car once that would run ok until he got on it and it would die out....turned out to be a flake of crude in the gas line creating an obstruction....

 

 

Possible pump going bad. I have seen mechanical pumps be ok but under load not be able to keep up with demand.

 

had the same problem in my mg, it was a crack in the fuel line before the pump.

 

Yep this is my bet

Also, as a long shot, check the sock filter in the tank. Many years ago, I had the sock filter break up and clog the line........as well as the filter

Bullshark

 

yeah thats in essence what my buddies car had....when we did the fuel pump delivery test inthe garage it was fine...but under driving conditons with the fuel slshing around it would block the line....that was a difficult one to diagnose

 

Hey Jake,
I had two similar problems. The first one was it would run fine until the car reached operating temperature and then it would run very bad but it would not die. This problem was caused by the vacumn advance unit that sits on the side of the distributor. The advance unit has a rubber diaphram and the diaphram had a small crack in it but would not leak until it was warm and flexible.

The second problem I had was the car would run fine for about 20 minutes or until it reached operating temp. Then the car would just die. Then the next day would start fine and run for 20 minutes more. This problem was caused by the ignition module in the distributor. This applies only on HEI systems. If you have never changed this part I would do so now and here's why. It's relatively cheap, easy to install. If you do install a new module remember to apply the dielectric grease under the module.

Like the other postings say you may have a fuel problem. If you do when the car dies and you look into the air intake of the carb you shouldn't be able to see any fuel squirt when you move the throttle back and forth by hand.
Good luck with your problem and let us know how you do.
Steve

 

Many years ago I had an Uncle who was a car mechanic. If he did not like you he would drop a ping pong ball in your gas tank. He drove a few people nuts that way...

 

check the fuel feed lines... sounds almost like the rubber lines are swollen up....

 

Bad plug wires.

Brett

 

check the pin in the accelerator pump, mine feel out causing the same conditions as you have...

 

I had the exact same experience. Checked fuel lines, replaced fuel filters, replaced spark plugs, swapped carbs, even replaced fuel pump only to find out that one of the egr bolts was loose and causing a major vacuum leak. Check your vacuum.