4.6 help needed

68GEETEE

5 Year Member
Nov 21, 2003
481
5
38
Texas, USA
I just bought a 98 Gt 5speed, stock motor. It cranks a very long time before finally starting. I found the air filter, throttle body and maf very dirty, so I cleaned them. The original plugs were worn out so I replaced them with new autolite platinum. The engine definitely runs smoother but it still cranks a long time before starting, what else should I look for? :shrug:
 
my 96 did the EXACT same thing... i will be willing to bet that it is your fuel pump, i changed mine and its like a brand new car again :nice:

the problem was the pump was letting fuel leak partially back into the tank, so there wasnt enough fuel pressure during the initial moments of starting, so the car wouldnt fire, after a second the pressure would come up and everything would be better, also if i sustained a highish rpm for a long time, then the car would start to ping, because the motor was drawing a constant amount of fuel (highway cruising, 3000+ rpm or more) so it would slowly trickle out again... this also went away with the new pump..

hope this helps
 
Green4.6GT said:
my 96 did the EXACT same thing... i will be willing to bet that it is your fuel pump, i changed mine and its like a brand new car again :nice:

the problem was the pump was letting fuel leak partially back into the tank, so there wasnt enough fuel pressure during the initial moments of starting, so the car wouldnt fire, after a second the pressure would come up and everything would be better, also if i sustained a highish rpm for a long time, then the car would start to ping, because the motor was drawing a constant amount of fuel (highway cruising, 3000+ rpm or more) so it would slowly trickle out again... this also went away with the new pump..

hope this helps

You may have a point. I have been listening to the pump activate when I turn the key on, but maybe its getting weak due to the mileage and age of the vehicle. I think I am gonna try changing the fuel filter first, I suspect it is the original, and if that doesnt work, I will take your advice and get a new pump. Thanks for the reply.
 
i would change the fuel filter and then maybe try a injector cleaner. at school we have this thing that taps into the test valve on the injector rail and you run the motor off of that for 20 mins, and it actually does a good job of cleaning out injectors.