96 F350 Died on highway

[JOAT]

The IDM may or may not be at fault. It worked enough to do a buzz, so it can't be completely bad

Start going thru the wiring. Especially the 12v+ wires from the battery. I think they are connected at the starter, but could be wrong. It may just be high resistance causing not enough voltage available while cranking.

Also you can swap the IDM relay with another. Or better check that the relay is supplying voltage still while you are cranking. Those relays cut out somewhere near 8v IIRC, but could cut off higher if defective.

 

[whatabudro]

I checked voltage at the valve cover plugs, just checked 2 of them. NO voltage. Checked the IDM relay *Good, checked Pwr and Gnd for the IDM both *Good.

How common is the failure of the IDM ? It is now pointing to the IDM isn't it?? Is there any place out there that will check the IDM? and How much do they usually run?

I've been fighting some IDM issues right now myself.

The Ford house was $719 list and through a friend of my dads that's employed there I was quoted $541.

I then got on ebay. I found several different sellers offering rebuilt IDM's for just under $400 with the return of your core in a prepaid envelope they provide.

I ended up finding another seller offering new old stock, still in Ford box for $275. It took about 7 days to get it but it was as described and in working order. The same seller has another one listed at that same price, however it's a part number for 99-03, don't quote me but I believe they will interchange and the newer ones are better because the voltage is higher to the injectors making them "snappier" That would be a good question for JOAT or some others.

Anyway here is the listing: $275 IDM

 

[JOAT]

...snip....

for 99-03, don't quote me but I believe they will interchange and the newer ones are better because the voltage is higher to the injectors making them "snappier" That would be a good question for JOAT or some others.

I seem to recall they all interchange, but get another opinion. The unfortunate side effect of the "Joe Servo IDM mod" being decoded is IDM prices have doubled on ebay.

Best bet, if you get to that point, is try someone elses (wish I were closer). First do all the wiring checks, and if you pull the IDM, pull the cover and make sure it didn't get water inside (been known to happen, especially on E-series.

 

[KansasDiesel]

The IDM may or may not be at fault. It worked enough to do a buzz, so it can't be completely bad

Start going thru the wiring. Especially the 12v+ wires from the battery. I think they are connected at the starter, but could be wrong. It may just be high resistance causing not enough voltage available while cranking.

Also you can swap the IDM relay with another. Or better check that the relay is supplying voltage still while you are cranking. Those relays cut out somewhere near 8v IIRC, but could cut off higher if defective.

I have already started checking wiring, and already swapped the relay with a known good one. and had checked it while cranking.

So the IDM is doing the buzz test the program is just telling it to? That is why I find it hard that the IDM is bad.

I might go ahead and pull the IDM out and open it up and see if I can tell if it's smoked.

fixed your quotation-whatabudro

 

[KansasDiesel]

I seem to recall they all interchange, but get another opinion. The unfortunate side effect of the "Joe Servo IDM mod" being decoded is IDM prices have doubled on ebay.

Best bet, if you get to that point, is try someone elses (wish I were closer). First do all the wiring checks, and if you pull the IDM, pull the cover and make sure it didn't get water inside (been known to happen, especially on E-series.

What is the "Joe Servo IDM mod" ?

Joat- I would love it if you were closer, Have you worked on these? and where do you find "someone elses" ? I did a yahoo search and coming up empty handed.

 

[whatabudro]

What is the "Joe Servo IDM mod" ?
an IDM mod that involves changing out internal parts to raise the voltage to the injectors. It's been a secret as to what the parts were and has been unveiled recently which caused a price spike in IDM's

Joat- I would love it if you were closer, Have you worked on these? and where do you find "someone else's" ? I did a yahoo search and coming up empty handed.
I believe he means if you know someone else locally with a working powerstroke that will let you swap theirs in for testing

I edited your above post also as one of the [ was missing causing the quote not to show up correctly. Also left a note

 

[JOAT]

Bryan

KD, here is FordForgotten's IDM mod page. He found that the Joe Servo mod, surrounded in mystery for years, was just one resistor to replace. Basically it fires the IDM quicker by increasing the solenoid voltage.

Not sure if I could fix a bad IDM. If I had a good one and a bad one side by side, a signal generator, and a scope, I might be able to get somewhere. I might also burn it up good

 

[KansasDiesel]

Bryan

KD, here is FordForgotten's IDM mod page. He found that the Joe Servo mod, surrounded in mystery for years, was just one resistor to replace. Basically it fires the IDM quicker by increasing the solenoid voltage.

Not sure if I could fix a bad IDM. If I had a good one and a bad one side by side, a signal generator, and a scope, I might be able to get somewhere. I might also burn it up good

LOL Like I haven't already burnt one up... (maybe)
Well I am going to take it out and let the electronics wizzards at work look at it and see if they find something bad.

 

[JOAT]

Couldn't hurt, as long as they take precautions against static. Some of the IC's are likely sensitive.

BTW I keep saying check the 12v, but of course grounds are equally important.

 

[JLDickmon]

Bryan

Not sure if I could fix a bad IDM. If I had a good one and a bad one side by side, a signal generator, and a scope, I might be able to get somewhere. I might also burn it up good

it's called "letting the smoke out"