7.3 dies hard/ no start when warm.

OBS-Addiction97 · Jul 29, 2021

Been helping a buddy try and get his truck running. Truck is heavily modded- 300-200, s475 etc.

When the oil temp hits 140* the truck dies and won’t restart unless starting fluid is used.

Replaced recently- ipr, pcm, cps, new adrenaline pump, new wiring harness and injector o rings.

Icp spikes to 2000+ After the truck dies and trying to restart it. Fuel pressure is good.

Im lost as to why it won’t stay running.

DEEZUZ · Jul 29, 2021

Try Icp sensor?

OBS-Addiction97 · Jul 29, 2021

CTC DEEZUL said:
Try Icp sensor?

Icp is Newer. No oil in plug and same outcome with it unplugged

Magnum PD · Jul 29, 2021

No CEL? Tach moving?

OBS-Addiction97 · Jul 29, 2021

Magnum PD said:
No CEL? Tach moving?

No cel.

The truck will run and idle up until 140* eot.

After 140* eot it won’t idle. It will run intermittently at 1200 rpm after it hits 140*, but will randomly stall and will only start on ether.

HAVOK9INE · Jul 29, 2021

OBS-Addiction97 said:
will only start on ether.

Does it stay running after, or does it just die again?

OBS-Addiction97 · Jul 29, 2021

HAVOK9INE said:
Does it stay running after, or does it just die again?

It’ll die again after it’s hit 140* eot.

Magnum PD · Jul 29, 2021

What does the temp say on the computer after 140?

OBS-Addiction97 · Jul 30, 2021

Magnum PD said:
What does the temp say on the computer after 140?

I don’t recall it doing jumping up drastically. It really wouldn’t stay running long enough after 140 to do any testing.

dsberman94 · Jul 30, 2021

If you have another ipr laying around try it. I had a similar issue years ago where my truck wouldn’t start back up a over 140 oil temp. Changed just the ipr coil because I didn’t have tools or time and it wasn’t an issue again.

dsberman94 · Jul 30, 2021

That is unless you already changed the ipr as a fix for this issue.

OBS-Addiction97 · Jul 30, 2021

dsberman94 said:
That is unless you already changed the ipr as a fix for this issue.

He’s swapped 2 or 3 IPRs on it.

Would low compression cause this?

Magnum PD · Jul 30, 2021

Need to find out what the duty cycle is when it wants to cut off

OBS-Addiction97 · Jul 30, 2021

Magnum PD said:
Need to find out what the duty cycle is when it wants to cut off

I had it on AE. It was between 15-20%. No signs of HPO leaks. HPO res is full also.

DEEZUZ · Jul 30, 2021

That's high too me

DEEZUZ · Jul 30, 2021

I'm wondering since it's so consistent if there is a control issue, aka PCM shorting out or something. But then you say it restarts on spray. Hmm

dsberman94 · Jul 30, 2021

I don’t think compression personally. I think electrical since it shuts off at 140 every time. At 140 the computer says it’s “warm” so it will turn off the ebpv at idle. Also the dash gauge should just be starting to creep up for coolant temp. Maybe ebpv wiring causing a short to an injector harness? Sounds like it makes sense anyway. Am I missing anything else that the computers change at 140?

Magnum PD · Jul 30, 2021

What would happen if you put a new oil temp sensor in? Maybe it’s doing something to the computer. Idk.

OBS-Addiction97 · Jul 30, 2021

Magnum PD said:
What would happen if you put a new oil temp sensor in? Maybe it’s doing something to the computer. Idk.

He just got one yesterday from Ford, I’ll have to follow up and see if he installed it.

OBS-Addiction97 · Jul 30, 2021

dsberman94 said:
I don’t think compression personally. I think electrical since it shuts off at 140 every time. At 140 the computer says it’s “warm” so it will turn off the ebpv at idle. Also the dash gauge should just be starting to creep up for coolant temp. Maybe ebpv wiring causing a short to an injector harness? Sounds like it makes sense anyway. Am I missing anything else that the computers change at 140?

Could be wiring, I know the harness is pretty new from Ford. No ebpv as the truck is T4.

Tested Lpo today and it was 50 psi at idle.