I have a 1996 F-250 PSD with manual trans and 120K miles. My truck does not wan't to start when the engine is cold. Normally around 55 degrees outside or colder, and seems to be worse at altitude (I live at 9000 ft, and work at 6000 ft.). I just changed the glow plugs last winter (about 9 months ago). I tried putting in a new glow plug relay, but did not help. The wait to start light runs normal time, and voltage drop seems normal while it on. Another symtom is that I get a ton of white smoke out of the exaust if I crank it a while. I have to use ether to get it to fire or keep it plugged in (block heater).

Any ideas what the problem might be or what to check?

Thanks!
tallen

 

Well hate to say it - but I'd say that it's still something glowplug related. The white smoke while cranking is fuel that isn't burning enough to fire. I couldn't tell you what to check next - but I'm sure someone more knowledgable in that area will be along shortly. Good luck!

 

Glow plugs-
connect a test light ground clip to your HOT post of the battery. A bad glow plug will not light the light when you touch the probe end to it. A bad glow plug will also burn very brightly, (as bright as when you touch the probe directly to ground) A good one will light, but not as brightly as when grounded.
glow plug controller-
check for voltage at the electrical plug on the glow plug
wiring harness under valve cover-
you can perform all the above tests through the wiring harness if you have the schematic.
Weak batteries (even though it turns over fast)-
HAve your batteries load tested at your friendly local parts store.

Do not assume your glow plugs are good just because they are new.
Hope some of this will help.

 

Man- CAtMan beat me on the hunt and peck this time!