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Yes, you should be able to monitor the voltage the PCM sees -- the outlet test monitors the input to the PCM and IDM, the main difference is if the meter reads quicker than the reading from the PCM

Those voltages sound "normal" to me -- what we were looking for was if the voltage dropped out before the engine failed -- I would have expected below 9 volts -- sounds like the voltage held, just lost the input from the alternator when the engine died

You could rule out the glow plugs by disconnecting one of the small wires on the glow plug relay -- that will effectively disable them -- do that after the engine is running and see if it will still fail

Electrical problems can be a real pain to find -- especially intermittent -- hang in there
 

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Discussion Starter · #23 ·
Yes, you should be able to monitor the voltage the PCM sees -- the outlet test monitors the input to the PCM and IDM, the main difference is if the meter reads quicker than the reading from the PCM

Those voltages sound "normal" to me -- what we were looking for was if the voltage dropped out before the engine failed -- I would have expected below 9 volts -- sounds like the voltage held, just lost the input from the alternator when the engine died

You could rule out the glow plugs by disconnecting one of the small wires on the glow plug relay -- that will effectively disable them -- do that after the engine is running and see if it will still fail

Electrical problems can be a real pain to find -- especially intermittent -- hang in there
You could rule out the glow plugs by disconnecting one of the small wires on the glow plug relay -- that will effectively disable them -- do that after the engine is running and see if it will still fail OK by relay do you mean solinoid? Like on top of the engine on the left side of center there's 2 solinoids. 2nd one back is for the glow plugs correct? Just take one of thr small wires off?
 

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Yeah, takes both small wires connected to the relay to make it operate -- removing one of them would render it inoperable -- be sure the little wire does not short out -- one is hot when the key is on (Red wire), the other is grounded by the PCM -- So taking off the ground wire is fine, taking off the hot wire has to be protected from shorting
 

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Discussion Starter · #25 ·
OK well I replaced the accelerator pedal assembly and the truck still dies when it wants to BUT, when it IS running and I mash the pedal to the floor, the engine responds accordingly and no CEL. Before when I mashed it, engine wouldn't respond at all, just continue to idle and I'd get the engine light on the dash. Once I let off the pedal the engine light would go off. So it appears I have or had more than 1 issue, I am also suspecting the new reman IDM. What are the chances both IDMs have the same problem?
Also pulled the driver's side valve cover to check UVCH. Everything looks fine there. I wanted to see all the injectors pissing oil but now I can;t get it to run long enough for me to get from where I can start it around to where I can see it before it dies. And now every time I do a buzz test, the relays click under the dash and I get test completed successfully. no errors found. And the damm injectors never buzzed. Not all at once. Not individually. Not at all. How can that be a successful test?
On top of all that, the stupid interior dome light won't shut off. all doors are SLAMMED shut. but that stupid [email protected]$Q light just tonting me to spill a lil gas on it....
 

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Discussion Starter · #26 ·
Oh yeah and I tried taking a little wire off the glow pkug solinoid, no change except I got a glow plug code so I put the wire back on.
What should I try next??????
 

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You have multiple problems -- sounds like one down ?? to go

Taking the glow plug wire off was to prove that the glow plug system was not coming back on and killing the engine -- or at least that is where I thought you were heading

With the relays clicking, still sounds like a power connection problem to me -- The "buzz test" should not click any relays
Having the buzz test complete "successfully" involves hearing the individual injectors click -- the software side of the IDM can complete without firing the injectors
The power driver side of the IDM can be fried (likely not the case here) or not connected and still show a completed test

Have you opened up the 42 pin connector at the rear of the engine to see if there is a problem there ?

Two IDM's having the same problem are slim to none I think -- Having a connection issue that is common to them is more likely
There is a test procedure that involves removing the IDM plug and using a meter to test the injector system as a whole from that plug
I attached it below
 

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Discussion Starter · #28 ·
WOOT WOOT! Well, she's finally running! Been driving it all week and she hasn't missed a beat. AND, when I start it now, it fires off Immediately. I mean like a super short, almost no crank time. Last thing I changed was the passenger side UVCH. The wires were all cracked and crumbly. Exposing the metal conductor here and there. I assume the bare spots were arking off causing a dead short. So new UVCH on passenger side and VOILA! Engine runs until I turn the key off. Haven't had any clicking relays and now it fires off as soon as the starter starts to turn the motor. I wouldn't say I had a long crank time before. Seemed like the engine made a whole revolution then fired. You know, like a typical 7.3l. now its like hit the key, and it's idleing. There's no crank time. no ramp up. 0 to 700 RPM's instantly. Oddly, the same 4 codes are still coming back. So there's still an issue. At least its worth fixing. Thanks guys for all the help.
 
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