Pinto Car Club of America

I have a 1975 2.3L that hesitates under acceleration.  If i punch it, the engine will cut out for about half a second then take off like normal.  I just rebuilt the carburetor so it should be fairly clean.  While it was apart, i soaked it in some carburetor cleaner dip stuff over night before re-assymbling.  It amost seems that the accelerator pump isnt working, but that was included in the rebuild kit so its brand new.  Other than a vacuum leak, or something else creating a lean condition, does anyone know of anything else that could be causing my problem i.e. timing, ignition, etc?

Check the spring in the accelerator pump, just to ensure it isn't in backwards.

Sounds like a fuel air mixture issue to me, but that's what most of my carb problems have been, so almost everything feels fuel air mixture now. :(

Does it run smooth during idle? It may be a vacuum leak.

Does it have an EGR valce? If so, check it out, it might be cracked or have a bad gasket to the manifold spacer.

Try and advance your timing and see if that helps.  I had the motor out of my cruising wagon over the summer to fix the flexplate and replace some gaskets.  One of the gaskets I replace was the head gasket due to an oil leak which meant I had to fool with the timing belt.  When I got it running again it had a huge dead spot in it.  I did not touch the carb so the only thing that changed on my car was the timing.  I kept advancing it till the dead spot went away.

It runs smooth at idle so im thinking its probably not a vacuum leak.  But the timing being off does kinda make sense cause we were messing with it awhile back.  Ill take it out again and try advancing the timing to see if i can get it to stop hesitating.  Ill probably also try richening it up a bit too.  Thanks for the help ya'll