So...I started my '01 F250, which was in my garage, and drove to work. The truck ran fine without any problems, ever. I come out from work to go home (at about 1 AM) and the truck won't start. I spend the next afternoon trying to get it to start, to no avail. The temperature was around 30 degrees during the day and about 10 when I tried to start it. I have had no problems all winter, in fact it started right up after sitting outside for 4 days during an ice-storm. Ideas? My mechanic has had it for 2 days and is stumped.

 

Have you checked the battery voltage?
Have you tried a new CPS?

 

What all has the Mechanic tried??

 

Initially the mechanic thought it was the CPS, but ran some tests and determined that this is not the problem. Now the mechanic thinks that it may be the GPR, but that the relay is not turning the glow plugs off and that they stay on. He thinks that this may have caused the plugs to burn out, but he told me that the plugs were so hot that they were smoking. He said that if he replaced the plugs the problem would remain and that the problem may be in the relay or the computer.

 

Have him check the Oil Temp sender. The pcm uses this to determine how long to run the plugs up to 120 seconds. Also the PCM triggers the plugs by sending the ground to the relay, make sure the trigger wire is not chaffed and contacting ground somewhere. Make sure he counts the tips on the glow plugs a burnt plug tip can break off and end up in a cylinder.