7.3 UVCH??

[cjken]

Just wast to see if anyone has experience testing and/or replacing the UVCH in a van.
I'm not sure that is the problem, but it is a 95 and It may be the right time to replace.
Van has been running great lately until Sunday.
I started it up it ran for about 30sec to 1 min then made a strange sound from the drivers side and stalled. No restart.
I'm thinking IDM since it is located on drivers side fender. Not sure if it makes sound when it fails.
The sound continued for a few seconds after it stalled which makes me think it is not purely mechanical.

I tried buzz test no sound and got codes
P1293 and p1294.
If it is IDM I want to make sure it is not something else that caused it to go bad.
Have not had time to pull out IDM.
Will hopefully pull it on Friday.
I have a spare IDM I can use for testing. Comes from a van that ran do I assume it is still good.

Any advice would be appreciated before I tear into it. While I'm in there I'd like to change out any parts that need it since it is an old truck.
Mileage is low, but it probably idled a lot and time takes its toll on wiring plastic and rubber in the engine bay environment.
My experience with the 7.3 is it either runs great or not at all.
I want to take the time to bring it up to a level of reasonable reliability for the summer months.

Thanks

 

[gtbensley]

I am curious to learn about this as well.

 

[naterry]

No personal experience but I've heard repeatedly that this plug (& updated shim?) and the CPS are both must have's in a 7.3 spare parts kit.

 

[cjken]

Thanks naterry

I think I found my problem!!!



How it got full of water is beyond me.
It is located in a really bad place. Basically in the fender well. Maybe the water came in through the connector.
I feel better that I probably don't have to pull the valve covers now. I guess at some point I should.

Any advice on sealing the replacement IDM up to avoid future problems??

 

[cjken]

All the burning/shorting occurred on the side that was mounted down. Makes sense since the water would have pooled on that side. I guess that the sound that I heard was the shorting/arching.




Found a vent that may have Ben where the water entered.

 

[gtbensley]

Yikes, might have to go check mine.

 

[Bbasso]

water penetration on that is common... A faulty design.

 

[EXPO365]

Sorry but I'm a 7.3 n00b, what controller is this? This looks like a concerning issue, I think I may want to try and prevent this for the future.

 

[cjken]

Still fighting this IDM/UVCH problem
Got re manufactured unit.
Haven't tried to start but ran KOEO tests get codes:
P1298
P1218
P1293
P1294
Carefully ohmed harness at IDM connector all checked out
All injectors buzzed when performing buzz test.
Have not tried to start truck yet.
I want to see if anyone has ideas about these codes before trying to run.
I would really like to avoid pulling valve covers but that may be the next step.

Any ideas out there???

 

[mgmetalworks]

Still fighting this IDM/UVCH problem
Got re manufactured unit.
Haven't tried to start but ran KOEO tests get codes:
P1298
P1218
P1293
P1294
Carefully ohmed harness at IDM connector all checked out
All injectors buzzed when performing buzz test.
Have not tried to start truck yet.
I want to see if anyone has ideas about these codes before trying to run.
I would really like to avoid pulling valve covers but that may be the next step.

Any ideas out there???

You cleared all of your DTCs first thing? These came up after you installed and finished KOEO tests with new unit?

 

[cjken]

I have the AE Scanner. When it first connects it shows no codes
Only shows after KOEO tests I'm not sure if they actually get stored in the IDM orPCM memory or if they only show from the actual test and are not actually stored.
I can borrow an ford NGS scanner Monday if that would be more accurate.
I was so confident it was the IDM since it was full of water and burned.

 

[cjken]

 

[cjken]

Any chance the shorting IDM could have damaged something up or down stream from it?
If it wasn't a van I think I would be more willing to dive into the wiring harness, but it is so hard to access everything.

 

[gtbensley]

Clear the codes first!

 

[cjken]

It lives!!!
Cleaned all contacts really well
Was getting intermittent connection to AE scanner so:
Swapped PCM with donor ambulance.
No more codes strong buzz test.
Tried to start. Did not run. Saw icp pressure was low. Checked HPOP it was low filled up with fresh oil started right up. Not sure why HPOP was low. Maybe drained it when trying to start prior to switching out IDM. I did crank on it a bit after IDM shorted originally.
Feels good to be running. Thanks for advice all!!!