More 7.3 OBS troubles.

[greenskeeper]

Right now the truck is totally DEAD, cranks but no start. In the morning I’ll pursue looking at all fuses and fuel bowl heat element being burned out. With the WTS light coming on as it was stalling out, the power supply to pcm stopping makes sense.
I did inspect the wire harness over the valve cover on drivers side. Looks just fine.
I’ll report back tomorrow with more.
Thanks for the ideas. It’s helping me.

are you getting the WTS light everytime you attempt to start? If so that proves the PCM is getting power.

if it was my truck, my next move would be to remove the passenger valve cover (easiest) and look for oil coming from the injector spouts...that would prove that the CPS, IPR, ICP, IDM and HPO are all working. My next step after that would be checking fuel pressure at the schrader valve with a tire gauge.

 

[greenskeeper]

The WTS is probably coming on because the computer is cycling the GPs again... since the ignition is on, and not running.

No. You can crank all day long and the PCM will never cycle the glow plugs a second time. WTS light only occurs when the PCM is powered up (key to on) for a set period of time based on a number of parameters mainly oil temp.

 

[m67tang]

Both 10A fuses under hood I’m touching here are blown. No other fuses I checked were blown. what do these go to?

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[79jasper]

Look like trailer lights.

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[m67tang]

Look like trailer lights.

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That’s what I was afraid of. Has nothing to do with my truck being dead.

 

[lotzagoodstuff]

….With the WTS light coming on as it was stalling out, the power supply to pcm stopping makes sense.

You mentioned that the WTS light was coming on as it was stalling out. This would suggest that your PCM is losing power and getting powered back on again. If it were me, I'd change the ignition switch. It's pretty easy to do and pretty cheap, and from a logic standpoint: it's one of the few things that could make your PCM lose power, which would explain your stalling/no start issue without any codes.

Good luck

 

[m67tang]

If I hook 12 volts strait to the IPR would it make a noise from movement to detect a bad IPR?

 

[79jasper]

I think it's pretty quiet. Just a electromagnet moving a tiny needle.
I'll ask again, are you viewing live data? If not, you're ******* in the wind.
Need to look at icp, ipr duty cycle, and rpm.

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[m67tang]

I think it's pretty quiet. Just a electromagnet moving a tiny needle.
I'll ask again, are you viewing live data? If not, you're ******* in the wind.
Need to look at icp, ipr duty cycle, and rpm.

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I only have the ability to read codes on this truck. I heard about the Forscan app and using a WiFi OBD plug-in. Will that give live data?
Also- with the truck NOT starting how will live data be of help?

 

[m67tang]

Will OBD FUSION app with Veepeak ble OBD scanner give me all the data readings on this truck??

 

[79jasper]

Forscan is great, but better if used from a laptop, the phone app is a shortened version.
For phone apps: torque pro and car gauge pro are great. If you have a android you need a bluetooth obd2 adapter. I still recommend the obdlink brand ones.
I think for iPhone you have to use the wifi ones, which again, obdlink brand.
You will still get values (or lack thereof) while cranking.

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[greenskeeper]

If I hook 12 volts strait to the IPR would it make a noise from movement to detect a bad IPR?

That’s what I was afraid of. Has nothing to do with my truck being dead.

Are you still getting the WTS light when turning the ignition to "on" ?

 

[m67tang]

Are you still getting the WTS light when turning the ignition to "on" ?

Yes, WTS still comes on and engine cranks, and smoke comes out tailpipe. It even tries to fire up. Then nothing.
I’m at a loss what to do next. Still no more fault codes.

I’m thinking about a pigtail to bypass the PCM and put 12 volts strait to the IPR. Just to check the pcm. Then a manual fuel pressure gauge off the fuel bowl to see if I’m getting pressure on fuel.

 

[79jasper]

You can feed the ipr 12v, just not too long or you will fry it.

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[m67tang]

If my IPR or PCM was bad, would I still be getting smoke when cranking the engine??