After warm up hard to restart

[DonN]

I have a 99 Expy with about 100,000 miles on her. She starts up fine in the morning, After full warm-up and you shut her down, it will turn over but will not start, after cycling the key on and off several times she will finally start, but this is my wifes vehicle and I don't want her to be stranded. Anyone else have this problem, and if so what was your solution.

Don

 

[toms89]

I have a 99 Expy with about 100,000 miles on her. She starts up fine in the morning, After full warm-up and you shut her down, it will turn over but will not start, after cycling the key on and off several times she will finally start, but this is my wifes vehicle and I don't want her to be stranded. Anyone else have this problem, and if so what was your solution.

Don

Sounds like a fuel issue or lack there of. Cycling the key will energize the fuel pump each time for a few seconds. I would have fuel pressure checked at the rail when the issue occurs.

 

[DonN]

I have already replaced the fuel filter, and when the truck is started in the morning it will run fine with no indication that it is starved for fuel. I am afraid to ask, where is the fuel pump on this, i have the 5.4L

 

[toms89]

I have already replaced the fuel filter, and when the truck is started in the morning it will run fine with no indication that it is starved for fuel. I am afraid to ask, where is the fuel pump on this, i have the 5.4L

In the fuel tank.

 

[DonN]

thanks for all the help, I guess I will be dropping a gas tank in my near future

 

[toms89]

Do you smell fuel when you get the no start condition??

I would check fuel pressure to confirm if that is even the issue or not before replacing any parts!!!
Even if fuel pressure is not correct... it is not necessarily the fuel pump.

 

[DonN]

yes I will check presure next time it happens before I do anything. My wife went to work tonight and it would not start for her. I got home and it took 3 attempts and it started. Now she left it with about a gallon of fuel in it, and I have told here several time, but she is not getting it, sucking up all of the crap in the bottom of the tank can't be good either.

 

[toms89]

yes I will check presure next time it happens before I do anything. My wife went to work tonight and it would not start for her. I got home and it took 3 attempts and it started. Now she left it with about a gallon of fuel in it, and I have told here several time, but she is not getting it, sucking up all of the crap in the bottom of the tank can't be good either.

The tank is sumped and it always picks up from the bottom anyways so would not worry about the "crap at the bottom" . It would always be there regardless It also has a sock style filter on the intake of the pump which filters out any large debree. . I replaced my pump for my build and tank and remaining fuel was pretty damn clean.

Running the tank dry could still potentially damage the fuel pump because fuel is what is used to cool it.. Not to mention the issues you will have with your air/fuel ratio if pump is intermittently sucking air. It doesnt take much fuel to fill the sumped area and pump intake but it can easily slosh around while the truck is in motion.

 

[toms89]

Just for curiousity..next time the issue arises hold the throttle on the floor and see what happens when you crank it. This puts it in clear flood mod and it will not inject any more fuel while the pedal is floored. This will let you know if it is flooding while hot.

 

[flyin]

I had one with a cylinder head temp sensor that wasn't reading properly. Similar symptom. I replaced the cyl head temp sensor and cleaned the harness where it connects. Coolant was leaking from the t-stat area and messing with the resistance and fooling the engine into thinking it was at a different temp than it really was causing a hard start issue