I'll try to make this short with enough information. Bought a used '99 f350 with busted rings and a bent pushrod on #5. Block and heads rebuilt, lots of shiny and go fast parts and Hydra chip. Finally try to start, just cranks. Troubleshooting pointed towards IDM. Swapped with a buddy, no chip this time. Buzz test passed. Truck started but sounded a little aggressive or rough at idle, not sure which. Shutdown, disconnected batteries, pulled the key, installed hydra chip, second IDM fails. If the PCM was flashed previously, could the hydra chip tunes be causing this with the stacked programming?
2 blown IDMs, after hydra chip install
- Thread starter Dscrant
- Start date
There is no such thing as stacked programming. I would be looking for electrical shorts, testing voltages etc. You can send your IDM to Swamps and they may be able to pinpoint where it failed and why and repair your IDM. Are you absolutely sure the IDMs failed?
Arisley
Moderator
On first star, a 7.3 is going to be very rough. Lots of air in the HPoil system.
I followed the pin tests for the IDM harness off of Alldata. Everything read fine, but definitely not ruling out a short. I'll send the first IDM out and see if I can get some info on failure point.
I know first start will have lots of air in the HPO system. Maybe it's just my mind reading more into it.
Just trying to get some fresh idea
I know first start will have lots of air in the HPO system. Maybe it's just my mind reading more into it.
Just trying to get some fresh idea
Arisley
Moderator
Personally, I would run it with no chip until I got all the air cleared out and checked for leaks, a retorque of the head bolts, etc. Stick a scanner on there and make sure everything is up to snuff. Then put the chip in. Double check the connector on the PCM and make sure you have it cleaned off well. Careful, don't remove the tinning. Good luck and keep us updated.
Thanks SuperPSD and Arisley. Sounds like a good way forward. I'm starting to think it's terminals on the PCM not being clean enough for the hydra. After all this writing and calling I've down, it seems a little obvious that the hydra was the only variable. Im going to run through wiring again, whole harness, inspect the PCM connection for the chip, and go from there. Does anyone know if the connections between the PCM and hydra will kill the IDM or would damage stay local to the PCM? Just trying to plan ahead. Can never have to many spare parts if everything checks out ok. I'll update as I troubleshoot
So IDM definitely fried. Old harness had fractures on VC connectors but nothing obvious or dangerous looking. Either way, have another IDM I'm picking up tomorrow, a new"er" wiring harness, im going to plug everything in and do some more voltage, resistance and continuity checks before I think of starting. Hopefully 3rd IDM is a charm. I'll post a pic of IDM damage as soon as I figure it out
Arisley
Moderator
What kind of shape are your under valve cover harnesses in. If you have to replace them, DO NOT use ones from parts stores. Most of these are made by Dorman and completely suck. Buy either Ford or International.
dsberman94
Well-known member
Get ford wiring gaskets and sensors. All others are junk and don’t last.
ghohouston
Active member
So what's causing the idm to fry? You could have a pinched wire beneath one of the valve covers. I suppose you could ohm out the uvch's at the positive pins and other probe on ground and see if there is continuity. That would be a quick easy check to see if that's causing the idm's to burn, although I'd expect to see burns in the uvch connectors as well.
DieselDC
Member
- Joined
- Jan 10, 2017
- Messages
- 401
- Reaction score
- 0
Should have replaced both valve cover gaskets. Chip, no chip it will start.
You have a short somewhere.
—————signature—————
~Don’t overthink something simple~
...:uptight people suck:...
You have a short somewhere.
—————signature—————
~Don’t overthink something simple~
...:uptight people suck:...
ghohouston
Active member
And thinking further, I suppose a solenoid could be shorted on an injector as well, so I'd definitely check my resistance on all 8 of them too.
Ok... got a new to me, very good condition engine wire harness. Pulled another IDM yesterday from a wrecked truck. I have the pin test for injection system from all data. Even though I dont have a DTC I figured it's a good place to start. Both valve covers are new, now, and all sensors were already replaced during the rebuild. I'll keep the updates coming as I make progress. Thanks for the ideas and places to start.
I hope the injector solenoids aren't bad, they're brand new with about 7 minutes of run time from Full force, 180/100
I hope the injector solenoids aren't bad, they're brand new with about 7 minutes of run time from Full force, 180/100
Ok, wiring harness installed, valve covers inspected, again. All injectors checked good 2.8 ohms, ground for IDM plug is good, wiring harness ohmed from IDM plug to injectors, everything there checks out. I've got the wiring diagram for IDM printed. Everything is checking good. Any advice on what to check next? I think I'm going to throw the idm and pcm in without the chip, buzz test, self demand test, (hopefully) start and go from there
Members online
No members online now.