Fuel Pump?

[surfaaron]

My car will only start if I push the pedal to the floor and even then it has troubles. I think it may be the fuel pump. How hard is it to change the fuel pump in my 87 mark. I have found the part and they are not cheap. Is there anything else I should replace while I am in there. Thanks for any help.

 

[NYC LS8]

IIRC, flooring the gas pedal to start the car shuts off the injectors. Do you hear the pump prime for 2 seconds when you turn the key to run? I would check for codes and check your fuel pressure at the fuel rail behind the alternator.

Aftermarket pumps (Walbro 190lph, etc) are only around $100.

 

[surfaaron]

I cant tell if the pump is running or not but I am going to take another listen. Why is it that pushing the pedal to the floor and holding it there is starting the car if it shuts the injectors off. It seems to get harder and harder for it to start as the days go byalso. How hard is it to replace the pump. They are in the tank are they not? Thanks for the info and the help.

 

[NYC LS8]

These aren't like carbed cars where flooring the pedal or pumping it will provide more gas to the engine. If you don't hear the pump prime for 2 seconds before you start it, it'll either be the pump or the relay.

The pump isn't hard to change at all in these cars. I've had my tank down more than a few times. I will say that it's a hell of a lot easier with hardly any gas in it. It's only 2 bolts that hold the straps for the tank up, then the tank will come down. If you do open it up to change the pump, be prepared to a lot of dirt and possibly rust on the top of the tank. When I replaced my pump years ago, I could NOT get the ring that holds the pump assembly back in correctly, and the tank was leaking gas like a sieve. I wound up just getting a new tank and being done with it.

 

[Gray Mist]

Have you checked fuel pressure? Changed fuel filter? Checked out ignition?

Before buying expensive parts, varify that the part you are going to change has the best chance of fixing the problem.

Or if you are going to through parts at it, start with cheaper parts than the fuel pump.

Fuel pressure guage would probably be worth investment.

good luck.