89mustangfive0

when i go to start my 89 gt it cranks...trys to run and shuts off.i noticed when i turn the key you dont here the fuel pump whine, but when i crank i have 42lbs of fuel pressure...i also check spark an i have it and i checked the injectors with a noid light and it lights up..the inertia switch is good and i also tried swapping tfi modules and it does the same thing... any suggestions? or so i have a huge wiring problem somewhere?? thanks

89mustangfive0

just went outside if i push the key foward right before it cranks..i hear the fuel pump go on...but if i dont physically push the key and hold it the pump wont go on..

bjlo4life

It may be an ignition switch ?? I know mine did something like like w/ the fuel pump and i thought is was the relay. Turned out to be the relay box where the actual relay plugs into. These are known to go bad. You can get one at the junk yard or go get a new one at napa for like $10. These relay boxes where the relay goes into have 2 grounds and like 2 hots. One hot constantly and one hot w/ the key forward so to speak. Hope this helps you out in your case.

89mustangfive0

i changed the igniton switch just before car wont run unless i hold the tumbler

89mustangfive0

ok so i chekced all the fuseable links and they are good...the new ignition switch didnt fix the problem...the car wont stay running unless i hold the key in a certain spot( where the starter disengages) the tumbler was replaced about a month ago and i noticed yesterday that the key turns foward alot more...is itpossible the tumblers f*cked up.

1slo8850

you could of got a bad tumbler , if the old one worked at all try that one