OBS wont start

mattymx · Feb 14, 2015

The truck has been dead for a few weeks because I have not had a lot of time to look at it.

WTS light comes on, tach moves, and a new GPR.

I am not getting any signs of the injectors firing. Nothing coming from the tailpipe like unburned fuel or smoke. A buzz test was ran and all 8 injectors are buzzing and sound great, but the App states IDM failure. I dont get that at all....

IPR duty cycle at start up hits 70% but I only show .25V ICP. I unplugged the ICP sensor and I get the same readings. Fuel bowl is full of fuel.

Could the IDM be bad if the injectors buzz? I'm totally stumped.

rusty1161 · Feb 14, 2015

I had a similar issue. Check the IPR wiring harness. My wires were bare from the insulation eaten away by oil/fuel.

Rusty

mattymx · Feb 14, 2015

Here is a photo I just took of a wire that was not connected near the IPR. I could not find where it was meant to go. Any ideas?

rusty1161 · Feb 14, 2015

Fuel heater/water in fuel/fuel restriction sensor?

Rusty

ghohouston · Feb 14, 2015

I think that's the fuel bowl heater wire. It probably shorted out on the previous owner, and he just unplugged it, or previous owner unplugged it out of fear of the heater shorting out

ghohouston · Feb 14, 2015

And have you checked all your fuses?

rusty1161 · Feb 14, 2015

rusty1161 said:
I had a similar issue. Check the IPR wiring harness. My wires were bare from the insulation eaten away by oil/fuel.

Rusty

Have you taken a good look at this?

Rusty

rusty1161 · Feb 14, 2015

This is not a very good pic at all, but shows the damage mine had.

Rusty

ghohouston · Feb 14, 2015

rusty1161 said:
Have you taken a good look at this?

Rusty

That too! The weather pack seal turns to mush/gummy substance after enough diesel gets on it. Ive seen it happen on quite a few 7.3's. While you're in there, check the tin nut on the ipr. Good luck, it's a royal pain in the ass to reach the ipr on an obs with the stock fuel bowl in place.

mattymx · Feb 14, 2015

rusty1161 said:
Have you taken a good look at this?

Rusty

I looked and could not see any issues. But since I have measured 70%DC on the IPR, I think the wires are OK.

From looking on google, that wire goes on the fuel bowl to a sensor that I do not have. And I am the original owner of the truck so it is not something that has ever been done by anyone else. Here is a photo of what it looks like is the wire in question.

Both wires on the side of the bowl on my truck are fine and in place. This is a third wire that looks to not have a home.:shrug:

ghohouston · Feb 14, 2015

Check ALL fuses next

rusty1161 · Feb 14, 2015

It might be the issue if you're showing 70% ICP and it won't start. Mine wasn't found until I pulled the connector out. I used an old injector plug from an old VC gasket I had laying around to replace it. I hope you find your issue soon. It must be a nice day up on the mountain with our little heat wave this week.

Good luck.

Rusty