Erratic acceleration/need help desperately

94scoupe

Registered User
My 94/5 spd with 70,000 on a crate motor from ford is running terrible. Sometimes just cranks and won't start but will start if pushed and the clutch popped. When running the bottom half of RPM's are dead and it sounds like starving for fuel, then it will suddenly take off like passing gear and really rocks the motor. At WOT in 5th it has little to know power. Was running great. Washed it, parked it and now this. No, didn't get the ignition wet or anything like that. My thoughts are maybe the TPS. The vac/pres guage reads as it always has no matter what he engine is doing. I have checked for vac lines off and electrical connections that are not tight or connected. Nothing there. Need help desperately.
 
balancer

Good thought. I had it replaced twice under warranty on the motor. I will check it out again. Hopefully that is not it. Things out of warranty now. Thanks for respondng

David Neibert said:
Start by checking the harmonic balancer.

David
 
Irratic acceleration

Thanks for your response to my question. I checked the balancer and it is fine. No wobble and not loose. Other things I checked over the weekend. Disconnected the TPS and car still ran but the problem was worse. Really sounds like starving for fuel until about half throttle and then takes off like it should at WOT. Disconnected the other sensor or whatever on the thottle body and no difference in running. Disconnected MAF and it runns but worse. Disconnected the Vac switch on left side fire wall and it made no difference. Does not appear to be any Vac leaks. Some times the car will not even start unless push started. Most of the time it starts right up but idles way high. Problem is getting worse. Any more ideas?
David Neibert said:
Start by checking the harmonic balancer.

David
 
94scoupe said:
Thanks for your response to my question. I checked the balancer and it is fine. No wobble and not loose. Other things I checked over the weekend. Disconnected the TPS and car still ran but the problem was worse. Really sounds like starving for fuel until about half throttle and then takes off like it should at WOT. Disconnected the other sensor or whatever on the thottle body and no difference in running. Disconnected MAF and it runns but worse. Disconnected the Vac switch on left side fire wall and it made no difference. Does not appear to be any Vac leaks. Some times the car will not even start unless push started. Most of the time it starts right up but idles way high. Problem is getting worse. Any more ideas?
idles high says vac leak check hoses in back of inlet plenum mine come off once in awhile and do this same thing it'll run rough then stumble and cut out top end not shut off but run like crap at 4k on iac may be bad,

oh yeah check connection at cam sensor
 
pull the codes on the car but im gonna say camshaft sensor....mine accelerated weird until i got it replaced...it sounds like your car is doing some more severe stuff though so that might only be part of it.
 
It might be starving for fuel...check the base pressure. Should be close to 40 psi with vacuum line removed from regulator. With line on and engine at an idle it should be something like 32-35 psi. With line on pressure should climb pound for pound with boost. Zinging the throttle hard enough to show 5 pounds of boost should show 45 psi of fuel pressure...10 pounds of boost should show 50 psi.

Could be the filter...the fuel pump...the regulator... or a leaking injector.

David
 
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