4AF (carburated) Hesitation when Accelerator Stomped
No problem with acceleration or hesitation, unless I stomp the accelerator
down (usually in an amergency situation) when the vehicle is idling.
Then I get about a second of nothing before the engine does anything.
Pretty sure accelerator pump is working because if I don't give the engine a
pump or two after it's been sitting parked for several days, it won't start.
(I.e., I stomp the pedal before starting the engine, something that would
have no effect on a fuel injected vehicle.) Maybe it's pumping too much fuel?
No problem with acceleration or hesitation, unless I stomp the accelerator
down (usually in an amergency situation) when the vehicle is idling.
Then I get about a second of nothing before the engine does anything.
Pretty sure accelerator pump is working because if I don't give the engine a
pump or two after it's been sitting parked for several days, it won't start.
(I.e., I stomp the pedal before starting the engine, something that would
have no effect on a fuel injected vehicle.) Maybe it's pumping too much fuel?
is it automatic?
otherwise I don't really see how that's possible...
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Does it sound funny when it does it? Like it is misfiring? because I get a similar problem. I have been trying to figure out what it is and at this point I am thinking spark plugs, cap and wires, fuel pump, the vacuum advance, or a combination of a couple of those things.
sounds like a transmission problem. when was the last time the transmission fluid was changed?
I don't see how it could possibly be a transmission problem. The engine
was idling during the problem period. The transmission didn't do anything
wrong. I.e., I stomp the accelerator and the engine idles/stumbles for
a second before reving up.
I could remove the transmission and still reproduce the problem.
Quote:
Originally Posted by freakinbox
Does it sound funny when it does it? Like it is misfiring? because I get a similar problem. I have been trying to figure out what it is and at this point I am thinking spark plugs, cap and wires, fuel pump, the vacuum advance, or a combination of a couple of those things.
Possibly, my attention is usually on the semi or train that's roaring toward
me, the threat of which caused me to stomp the accelerator in the first place.
I'll have to check for that in a safe area to see whether you're right.
Looks like you haven't isolated it either.
I recently put in new NGK resistor plugs gapped to 0.043 so I don't think it's the plugs.
yeah but we may also have 2 different problems, mine doesn't happen at idle. But sometimes pops up with the pedal not to the floor, or around 6000 rpm just seems to start missing like crazy and I have no power. I did the carb gaskets, so it wasn't them. Fuel pump seems to be supplying enough fuel. So I am thinking the vacuum advance in particular for my situation.
you can't adjust the air/fuel mix without drilling out the plug, wouldn't suggest it for anyone who isn't really good with power tools, go to far and you will drill into the screw!
No problem with acceleration or hesitation, unless I stomp the accelerator
down (usually in an amergency situation) when the vehicle is idling.
Then I get about a second of nothing before the engine does anything.
Pretty sure accelerator pump is working because if I don't give the engine a
pump or two after it's been sitting parked for several days, it won't start.
(I.e., I stomp the pedal before starting the engine, something that would
have no effect on a fuel injected vehicle.) Maybe it's pumping too much fuel?
I think I've seen this in other cars, my 4A-F with the same 3 speed does about the same thing, and 2 late 80's Camry's (4 cylinders). I even think airplane engines (4 cyl boxers) will do it too, if you hit the throttle too fast it kind of "floods" the engine with more fuel than it can burn for the rpm's? That's maybe a 1/2 second or so of the bogging no-go, then it spins up. If it's a lot longer then something does sound wrong.
Try smoother stomping, and look carefully for trains & trucks before pulling out If it's anything fixable, I'd want to try it out on mine, (as long as it's cheap & easy, I almost never notice the hesitation)
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