Misfiring and bogging when "punched"

Waterbury

Waterbury

True Classic
I have gone through a couple of possibilities now but can't seem to fix this issue. Whether it be at idle or in gear my car does not like it when I push the throttle from 0-50/60% quickly. It will begin to bog and hesitate. If I hold the throttle down it usually will die. If I gradually increase throttle I don't have these issues. In turn, for me to drive this car I have had to run it at pretty high rpms.

It idles just fine, only happens when I punch it below 4k rpms or so. Anyone have any similar issues like this before? Thank you
 
I'll assume you have a carbed car.

If that is the case I would strongly suspect a fault in the accelerator jet circuit. This is the circuit that squirts fuel down the carb to compensate for the slight delay in the main circuit when the throttle is snapped open.

Good luck!

Rob
 
If it's FI - then I'd check the air flow meter flap for sticking condition, beyond obvious things like dirty air filter, fuel filter, worn spark plugs, dist. vacuum advance disconnected/cracked.
 
Waterbury said:
I have gone through a couple of possibilities now but can't seem to fix this issue. Whether it be at idle or in gear my car does not like it when I push the throttle from 0-50/60% quickly. It will begin to bog and hesitate. If I hold the throttle down it usually will die. If I gradually increase throttle I don't have these issues. In turn, for me to drive this car I have had to run it at pretty high rpms.

It idles just fine, only happens when I punch it below 4k rpms or so. Anyone have any similar issues like this before? Thank you
Click to expand...

Please describe in detail what physical aspects of the FI system you have visually verified to be 100% correct; then please describe what measurements (such as fuel pressure, resistances, etc ) you have taken and how they compare with specifications.
 
Turned out to be exactly as joe suggested. The air flow meter flap was a little cruddy and needed cleaned up. Prior to that I had checked all fuel lines and cleaned the air filter. Replaced; fuel filter, fuel pump, spark plugs, wires. I still have the issue occasionally, but no where near the same magnitude.
 
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