I have a 74 I6 200 mav. The car idles great in drive and in park, but when in drive i hit the gas pedal and the car just stalls out and dies. I just replaced the EGR valve and carb. and still it does the same thing. i have checked hoses for air leaks but nothing seems to be wrong. i have checked the fuel system and no problems there. when i play with the gas in drive i can get the car up to speed, past 30 or so and it runs fine, it only stalls at a certain point an early point. I was thinking maybe choke, thats the only thing that i have not checked or messed with. any ideas or solutions would be very helpful.
if fuel lines/fuel filter are clear, and the fuel pump is working then your getting gas to the carburetor and 8 times out of 10 its the carburetor. I've bought rebuilts from auto stores before and they all had something wrong , your best bet is to clean and rebuild the carburetor yourself. I prefer the carter YF, very simple and generally lasts 75,000+ miles between rebuilds.
and I wouldn't think the choke would be the problem, I've driven all of mine without chokes installed or functional, the only time I need a choke is when it's freezing cold outside .
it could be a weak spark. the coil could be going bad. if it still has points they could be worn out.
i got the car about 2 months ago and the first thing i did was change the coil and plugs but i didnt change that plug wires. I just put a rebuilt holly carb on it a week ago and that helped put didnt solve the problem. I have put a new fuel pump and filter on it and checked the line no problems there. i have not thought about the accelerator pump. i will check that out tomorrow, is there any way to check it before i go out and find another one. also it could be the carb, i will get ahold of the place i got it from and see what there return policy is.
Slow down a minute - a good diagnostic plan will save you a ton of cash. Does it happen only when cold - if yes then it is likely the choke adjustment. If it happens all the time it could be your idle adjustment - if you can't adjust it is fairly inexpensive to have a shop do it properly - when you can find a shop that knows how to adjust a carb. If you have a vacuum gauge and some patience you can adjust it yourself. It might also be that you messed up the firing order when you replaced your wires - though it is not likely because you said it runs ok above 30 mph. Since it is a rebuilt carb it is possible that the accelerator pump is not adjusted properly - you can do this with a bit of care. It is more likely that the throttle shaft or bushings are worn and causing an air leak when the throttle moves. This requires a new throttle body unless you have the reamers and bushings to fix it. It could be insufficient ignition timing at idle - try disconnecting the vavuum advance and setting the timing. Since you have not complained about it running poorly once it gets up to speed I would guess the fuel pump and coil are in good shape. It may be more than one of these combined (unlikely) so fix the cheap things first and go from there.
