84' RC hesitation & stalling

[Copper]

318 - holly 2bbl.

It'll choke and stall out when you give it gas to cross an intersection. Often, if you back off the pedal it will continue running after the lag, not always. You can usually succeed by babying the accellerator pedal, even then it may be a bit rough.

It idles quite well. It seems fine once you get it up to highway speeds.

I suspected the EGR valve was not operating or was stuck open during acceleration, so I checked. The EGR valve is functioning (opening & closing) fine with manual vaccum. It's closed at idle and opens with increase in rpms. There is no change in the idle when you open and close it with manual vacuum. I'm guessing that means the passages are clogged. I may be wrong, but I'd guess that would not cause the hesitation/stalling problem.

It's been years since I've had an accelerator pump go out. I can't remember the symptoms being quite this pronounced. Could that be the problem?

Any other ideas?

Thanks

[KRB64]

That's what it sounds like to me. Pedal calls for more power, thottle opens, venturi sucks in more air but the accelerator pump won't compensate with the extra slug of fuel so the motor sputters and hesitates. When you back off it recovers. Once it's up to speed theres no need for the pump so she runs fine. My $0.02.

[DODGEBOYS]

yup l,d say bad excell pump also

[Copper]

Thanks for the input. I've pretty much been through the rest of the systems. With your confirmation, I'm pretty sure it's the accelerator pump. It's internal, so I'm just going to do a rebuild while I already have it half apart.

While digging, I found the air injection tubes were rusted through behind the engine, so I've decided to desmog it. It's amazing how much crap they added from the mid 70s to the mid 80's. I'm actually finding an engine under all that stuff.

[KRB64]

It's amazing how much crap they added from the mid 70s to the mid 80's. I'm actually finding an engine under all that stuff.

I had a '79 Ramcharger for awhile. I was cruising down the highway one day when smoke started coming from the dash. I immediately pulled over and shut her off. Popped open the hood and all along the firewall and fender was melting and smoking wires like the beginning of Mission Impossible. Once it cooled down I cut them all off, started it up and drove her home...