2003 7.3L cold start troubleshooting

[cstoesz]

New, and First Forum ever..... troubleshooting my relay/solenoid and did prescribed test from earlier posting accross the larger posts of the solenoid for the glow plugs and air preheater. Both had no voltage drop when key in on position... still 12V. Anyway to tell if its the PCM or the glowplugs without pulling out glow plugs or buying a new relay/solenoid? NAPA price for Solenoid is $225.

[cstoesz]

Wrong price on relay from NAPA. looks like 70 bucks. I'll try replacing the relay first, since the PCM is $497

[vitalidle]

If you have 12 volts going in and 12 volts going out after you cycle the key then its not the glow plug relay. Truck won't start or is it hard starting right now?

[SCUFFY828]

first off before you buy any parts , need a little better description of your problem and exactly how you tested it, and its not your pcm gauranteed,

[HillBillyDelux555]

Umm... don't know if this will help any, but had trouble startin my last winter. Have u checked the air filer and oil. Thats all that was wrong with mine!! Also, try plugging it in if you haven't, or put it in a shop that has heat if you got one. Hope I helped!!

[cstoesz]

I can only get the 7.3L diesel started if I plug it in or use ether (not too good) once the outside temp is below 55 degrees. The relay/solenoid can be heard exercising when I energize it on the bench, but when it is in the vehicle I get no power to the glow plug side or post. Therefore, I am thinking that I have a faulty relay or bad wire (not as likely) ar a bad PCM, (also not as likely)

[HillBillyDelux555]

What year is it? You should plug it in, that is what the plug is for, starting it in the cold weather. Mine won't start if it aint plugged in if it is cold. & did u check the air filter, try that before you go spending the big $$$.

[vitalidle]

When the relay is in the truck and the key is cycled on with the wait to start light on you should have power to the two big posts and the two little ones also.

[cstoesz]

New relay now and I now have voltage to all posts with the key turned to start. I just avoided having to mess with glow plug replacement. Thanks