royalcrown

Hey everyone. All of a sudden my car seems to hesitate a bit under acceleration at lower rpm's. For instance after shifting into gear (when the rpm's are low) and i accelerate i can kind of feel and hear the car hesitate over and over as i give it gas until i get into higher rpm's. Once I'm in the higher rpm range, the hesitation stops. Another example is that when I'm on the highway in 3rd gear (my top gear) going 65 there's no hesitation when i'm on the gas, but if i slow down to 55 in the same gear (rpm's are now lower) i can feel the hesitation when i give it gas. Also, when i'm sitting at idle, the car appears to be rocking side to side a bit more than usual. that could be my imagination but i'm pretty sure it started at the same time as when the hesitation started. When I'm coasting the car runs just fine. The best explanation I can give for the "hesitation" i'm experiencing is it kinda makes you rock forward and back in your seat as you're accelerating. Anyone know what my problem might be? I'm a little worried to drive it right now...

Starfury

Sounds like lean hesitation/misfire. What kind of motor/carb do you have?

1965fastback

Or a out of adjustment acel. pump on the carb.

royalcrown

It's a 289 with the 2 barrel carb

1965fastback

Or it could be a low float level.

kalli

noting to do with accell pump if it jumps at idle and low rpm cruise.
It's either running too lean, or too far advanced. maybe somethign stupid happended that the contact breaker plate got loose or the contact breaker came out of whack or it's with the carb.
That could be either float level or something blocked with dirt or a vacuum hose fell off or got broken.

1965fastback

After I read what i wrote i realized that.

Starfury

I agree with Kalli. Start by checking the timing, both static and dynamic. Report back with the results.

If the timing checks out, check float levels. If the float levels are ok, a carb rebuild is probably in order. Easy job on a 2100.

gmac429

Hey royalcrown. My 2005 Gt was doing the exact same thing. The local Ford dealership could not find the problem. A guy on Edmunds.com was also having the same problem also. He had his local Ford dealship replace the Throttle Position Sensor(TPS) and it solve his problem thus far. I done the same thing. I took the car in to our local Ford dealership for them to replace the TPS and now the car runs 100% better. It feels like it has more power. So far the problem have not returned. It will cost approximately $100 to have that TPS replaced. Good Luck.

boogerschnot

Thats good feedback, but this is the classic section. He probably doesnt have a fuel injected motor. Its most likely a carburator.