Im at my wits end and hoping anyone can help!!

My truck stopped running a few weeks back.
It was running fine... then I made a stop at the store and now nothing.

After much time I disconnected the fuel line from the fuel rail and turned on ignition and got no fuel. I replaced the fuel pump, ASD and fuel system relay but still no fuel. I have sprayed starting fluid in the intake and it does run for a second or two.

Since the system is run by the PCM does anyone know "EXACTLY" what sensors has to have a valid signal coming from them to get the fuel pump to come on. It should at least run for about 3 seconds once the ignition is turned on.


I do know there isnt alot of fuel in tank and my fuel light is on. Is there any low fuel cut-out built into the fuel pump module to keep from running completely out of fuel? Im sure the fuel level has been this low before.

 

No low-fuel cut out. It will keep running until it actually runs OUT of gas.

If the pump isn't even priming.... I would look at fuses first. I think there are a selection that actually control that circuit, one for power feed in the PDC, and another fuse on the control circuit in the junction block. (side of the dash) I think that one is fuse 9?

 

I 2nd the fuses, the dealer I bought my truck from replaced both o2 sensors in my truck trying to get the SES light off. I drove it for a few days, decided to check the fuses and found a burned out fuse in the o2 sensor position. Stupid dealer spent way more on sensors and a illegitimate inspection than he needed to.

 

If fuse and realy is good, you should be able to remove cap from fuel tank, turn key to ON, and listen and hear fuel pump at tank. If you cannot hear it, it ain't running. Either no power or pump is bad.

And a safer way to check fuel pressure is with a gauge on the fuel rail.

 

It's a 97, so most likely has a plastic fuel rail. Need one of these and a gauge with a quick disconnect on it. http://www.aetools.com/star-brand/51...yslerford.html

 

I see only one fuse in the fuse box under the hood... Dont see one listed for fuses in the dash... They all check out OK..

Are you saying that if fuses and relays are good that the fuel pump will run regardless?

Since the whole truck is computer controlled I cant believe that there is not some sensor keeping the fuel pump from running... Ive checked everything else I can think of....

Surely someone else has had a similar problem and knows what is going on...

 

I see only one fuse in the fuse box under the hood... Dont see one listed for fuses in the dash... They all check out OK..

Are you saying that if fuses and relays are good that the fuel pump will run regardless? Ive even pulled the fuel line off the fuel rail and get no fuel.

Since the whole truck is computer controlled I cant believe that there is not some sensor keeping the fuel pump from running... Ive checked everything else I can think of....

Surely someone else has had a similar problem and knows what is going on...

 

Sorry, but there is no sensor for the fuel system. And no, if a fuse and or relay is bad the pump will NOT continue to run.

 

The cam and crank sensor need to be seen before the fuel pump will run, BUT a bad cam or crank sensor will not prevent the pump from priming when the key is turned on. If it isn't priming, the problem is elsewhere.

 

Any idea where else to look... Fuses are good.. relays are good(i also jumpered the relay contats) and the fuel pump is new...

Only thing I havent checked is the ground to the fuel pump... Ive looked at the chilton manual electrical diagram and dont see anything that gound be a problem