Weird start up issue... 97 dually F-350 OBS

[Joe momma]

Hi there. I am a new member of powerstroke.org, I've been lurking the forums for a few weeks though, and I finally decided to join!

I have a 1997 Ford F-350 dually (extended cab) XLT model. And I have a weird starting problem in the mornings. When I warm up the glow plugs and I crank it, it seems like it WANTS to start. For a second you can hear the engine get very very close to the operating RPM. But then half a second later, it dies down, and half a second after that the rpms go back up again. Some white smoke starts to come out from under the hood while I do this. After 3 or so key turns the engine starts and the truck runs like a dream.

What could be causing this issue? The truck has 333k miles if that helps.

[Patrick Feeley]

Sounds like a glowplug system issue. I would first look at the glowplug relay and see what the voltage drop across the relay's large terminals are. Use a multi-meter with one lead on one of the relay's large terminals. Put the other lead on the other. When the key is turned to Wait-to-Start, read the DC voltage reading on the meter. Anything more than 0.3V and the relay is bad. Cheers!

[Joe momma]

Originally Posted by Patrick Feeley

Sounds like a glowplug system issue. I would first look at the glowplug relay and see what the voltage drop across the relay's large terminals are. Use a multi-meter with one lead on one of the relay's large terminals. Put the other lead on the other. When the key is turned to Wait-to-Start, read the DC voltage reading on the meter. Anything more than 0.3V and the relay is bad. Cheers!

I don't know... Doesn't seem like it would be a glow plug issue... I think haha. Some days it starts on the first hit. Some days regardless of how many times I cycle the plugs it takes a few tries before it starts. And when I start it, none of the cylinders seem to be missing. Lets me assume that each cylinder is getting warmed up properly. Like I said before, on the key turn it really seems like it will start. But it does kind of a loap or something and just before it can get to operating RPMs it just goes back down to 0 rpm on my dashboard. Very weird issue.

[Joe momma]

Also I want to add that SOMETIMES when I flip between the 2 fuel tanks it starts up in less than half a second. But it works only about 65-70% of the time. Not all the time.

[madpogue]

If you're "cycling" the glow plugs by turning the key off when the WTS light goes off and then turning it back on, you're wasting your time. The glow plugs stay on long after the WTS light goes off. Just leave the key in RUN for an extra several seconds for extended GP run time before starting.

The smoke under the hood is NOT right. Your best bet is to have an assistant try to start the truck while you observe under the hood, and determine the exact source location of the smoke. That might tell us something.

[zROCK]

White smoke from under the hood could be your turbo to downpipe clamp.

[Joe momma]

The smoke does seem to be coming from the turbo area. The past few days though it started right away, with no issue.