Osmossis

i am stumped i have tried everthing and connot locate he problem. I have a 1993 MGM now when i accelerated of a light or when i floor it while driving my car just hessitates then i let off the gas and apply it lightley it will go but very slow once im over 20kph or so it will be fine it happens all the time in hot or cold weather. I have replaced the following to try to fix it. Fuel Sending Unit/Fuel Pump, Fuel Filter, Fuel Pressure Reglator, Plugs Wires and DIS Coils. now when i rev it you can hear a sucking noise under the hood can a vacum leak cause this? any ideas would be greatly appreciated.

~Ozzy~

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~Ozzy~

 

redneckat

a vacuum leak is exactly what it sounds like to me I had the same problem in a 78 cougar.

Osmossis

update, i changed the EGR valve no change. I tested the TPS sensor now according to the specifications in the manual at idle is shoul be at .5V and at wide open throttle 5V, howver my TPS mesures at 5V all the time, now when i drive my vehicle the check enging light comes on at acceleration after the hesitation but once i coast it goes off do you think it is that sensor, can i drive without it to see if it works? any ideas would be appreciated.

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~Ozzy~

thefonz

Check for codes or pending codes. If your tps isn't giving you the readings it is supposed to, I would suspect that is your problem. Of course, if you have a vacuum leak, fix that first.

89LX COUPE

try cleaning mass air meter with electrical parts cleaner.

kaboom10

Change the fuel filter too.

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2002 5.4L F-150 4wd
Baer rotors w/ carbon kevlar pads, Amsoil filter w/modified air box,
Thrush glasspack muffler, Optima battery,
Kenwood radio, Livewire tuned, Edelbrock shocks,
4R70 trans kit, 4.88 TruTrac rear carrier, Accel 21lb injectors.