cold starting help

[jbajek]

i have a 2001 f350 7.3, had problems last fall with cold starting wouldn't start with temp. aroud 40, found out that the glow plug solenoid was bad, replaced it and day or two later the new one stuck on and drained batteries, got new solenoid from ford and two new batteries it was better but didn't want to start now around 32-34 degrees so i figured a couple glow plugs were bad cause with it plugged in it fires no matter what. So i just finally got around to changing glow plugs, solenoid (again just to be safe), valve cover gaskets and harness under the cover and still same problem. Now if i go out in the morning when its cold i crank it for 3 or 4 seconds then turn key off and do the routine a second time (key on, wait for light, crank engine) it fires immediately. I checked all new glow plugs and they have readings of around .9 ohms. I also checked to make sure that the solenoid is staying on long enough for the glow plugs to get hot and it is. The only other thing i have to check tomorrow is to make sure there is voltage going to the glow plug harness and to make sure that when the solenoid stuck that time that it didn't burn up one of the fuseable wires going to it. Just want to make sure im going in the right direction. Any help would be greatly appreciated.

[jc82chevyman]

It sounds like you got it covered but next time go with Stancor relay it is huge and will last longer

[firefighter317]

what wieght oil are you using?

[jbajek]

I am running Amsoil 15/40 synthetic, been running it for a few years now.

[firefighter317]

ok just making sure. if you use the wrong viscosity oil, it can cause no/hard starts since the injectors require 500 psi to operate.

[BuckedUp154]

Ive been having an issue like that too. Truck started fine until this morning, battery gauge sits at normal, then after a few seconds, the gauge drops and the truck wont start. Confuses the chit outta me. Maybe batteries going bad?

[firefighter317]

check the wire between your gpcm. Make sure your gpcm isnt faulty.

[firefighter317]

Also check the Glow Plug Control Module connector. Ford has a TSB about it and if the connector is damaged in any way, you are supposed to replace the connector with one fitted for the 6.0L. Check the quality of your fuel for gelling also. That would cause cold start problems.

[JHALL]

Originally Posted by firefighter317

Also check the Glow Plug Control Module connector. Ford has a TSB about it and if the connector is damaged in any way, you are supposed to replace the connector with one fitted for the 6.0L. Check the quality of your fuel for gelling also. That would cause cold start problems.

Where is the GPCM located?

[firefighter317]

should be on passenger side valve cover