truck has intermittent start issues

[dave feola]

hey folks have an 02 st with 87,000. for the third time now my truck has not started it cranks but will not turn over. I had it to shop twice, pressure tested fuel pump etc. could not find any problems. I just went out after truck was sitting for about 2 hours and it starts right up ?. has anyone else exp this. Thanks

 

[scott degroot]

Find a shop that knows how to do a proper current ramp test on the fuel pump. Most idiots out there have no clue how to do this and they rely solely on fuel pump pressure to determine a good pump from a bad one. If there is a fuel pump issue this test will find it.



Your symptons are a good example of a failing fuel pump but they are also symptons of a failing crank sensor (Ford usually doesn't have issues with these though) If I were a betting man I would say fuel pump before anything else. Others will chime in here also and tell you to check your inertia switch, while this is a good idea I have only replaced one that I can remember on a customers vehicle. truly I don't think that they go bad but otheres here swear that they have had them go bad....maybe it's got something to do with the weather...seriously.

 

[Kevin Palmer]

Try your other key to ensure it is not a lost program issue.

 

[Richard L]

If your truck is hard to start after sitting overnight or after sitting for 6-8 hours, but starts fine if only sitting for an hour or two, then you probably have a leaking fuel pump.



This is a common problem with the early 2001-2002 Sport Tracs.



If these are your symptoms, then try this. After the truck has sat overnight, turn on the key but don't try to crank the engine. If you have a good ear you may hear the fuel pump running. After about 10-15 seconds turn the key completely off and then try to start the engine.



The leaking fuel pump problem allows fuel to leak back into the tank which lowers the pressure in the fuel line. If you attempt to start without enough fuel pressure the engine will not fire. Turning on the key for 10 seconds or so allows the fuel pump to build the pressure back up. Turning the key off before trying to start the engine ensures that the computer has been reset for the next attempt to start.



...Rich

 

[dave feola]

the truck only does this after driving for an hour. shut it off go on for about 10 minutes,then come out and it won't start. wait about 1-2 hours and it starts fine

 

[Nick Miller]

My 02 ST had the same symptoms as yours. I changed the fuel filter and I have not had any more problems(knock on wood).

 

[Kevin Palmer]

You are describing a common fuel pump issue.



Basically, it heats up and partially shorts out within itself or it physically expands to the degree that it affects the impeller.



Test it cold for both pressure and volume, then do it after you get it good and hot and see how different the numbers are. It will at the very least tell you if you are headed in the right direction...

 

[dave feola]

Should I replace the fuel filter as well for arguments sake ?

 

[Todd Z]

The right thing to do is check it out, BUT the filter is cheep and easy, I would change that first..



Todd Z