PLEASE HELP...difficulty starting

[ZZYZXXXX]

Good afternoon,

I have a 99 Explorer XLT. Recently it has been very difficult to start. I read somewhere that it might be the fuel pump but I am unsure how to check for sure. I have to turn the key on and off a few times, which I assume pressurizes the fuel rail, then the truck will start. At times, it will start immediately, without turning key on and off. Other times, I will need to cycle the key on and off once or twice, other times, I need to do it 10 to 20 times. I cannot hear the fuel pump turn on but I was never able to hear it turn on and I have had this truck for ten years. I am assuming the fuel pump is to blame but I wold prefer to diagnose the problem and be completely sure rather than just change arbitrary parts in hopes of getting it right. What should the fuel pressure read at the fuel rail? I assume there is a valve on the rail I can get a reading from? Thanks for any and all help. I am starting to worry that I will get stuck somewhere and need a tow home.

Joe

 

[dimension12]

It is possible the pump is weak or the fuel pressure regulator is leaking.
What engine do you have?

 

[ZZYZXXXX]

I have the SOHC. Any suggestions on how to check them to see if they are the problem?

 

[ZZYZXXXX]

By the way, I do not have the check engine light coming on. I put my code scanner on it and no codes are coming up either.

 

[dimension12]

When it does start, does it run normal or do you have to give it some gas to clear it like it is flooded? If it runs normal the fuel pressure regulator is good.
You will have to hook a pressure gauge to the fuel rail to test the fuel pump. The fitting is on the driver's side of the intake. Off hand I do not remember the specs but you should have pressure when you crank the engine.

 

[ZZYZXXXX]

When it does finally start, it runs fine. That is what made me think it might not be the fuel pump as I figured it would stall out or sputter but it does not. What about a cam or crankshaft sensor? Not sure the sensors would be affected by cycling the key on and off though?

 

[dimension12]

I would be willing to bet it is a week pump. The sensors will work or not.

 

[ZZYZXXXX]

Is there a trick to pump up fuel pressure in case I cannot get it started...just until I swap out the pump?

 

[Lube]

Is there a trick to pump up fuel pressure in case I cannot get it started...just until I swap out the pump?

Unfortunately, no.

 

[intelisevil]

I had a problem that started similar to yours about 8-9 months ago. I replaced a few parts chasing the problem with no cure. Finally last week the check engine light came on, code P1507. I did some research and found this thread:

http://www.explorerforum.com/forums/showthread.php?t=84220&highlight=clean+iac

A $5.99 can of electrical parts cleaner and 20 minutes later my Exploder starts, idles and runs like new (almost 190k miles!).

Even if this doesn't fix your problem, it can't hurt.

Good Luck!

 

[G-96XLT]

One thing you can do if you have wires and a battery is feed power directly to the pump harness for a second or two. It should power up right away and with a hollow tank you can hear a nice whirl. If the thing sounds slow or has no whirl or it takes a bit to wind up then you can bet the pump is dead. Did you say 10 years, that is long time for a pump. I had it go both on the 96 and 2000. The 96 just died in mid traffic and the 2000 died slowly in the garage and it sputtered for a few seconds if I kept on priming before the starting