Stumped again

[psduser1]

I've run into an issue that has me stumped... crank but no start.
02 excursion, I've replaced the injectors with remans from unlimited.
The originals were 260k miles on them, and actually ran pretty well. The truck is going up for sale, so I figured new injectors may help move it. I put everything together under the valve covers and put the charger on it to hold the batteries at voltage.

I sent the ts6 out for reburn, so stock tuning.
So far, I've checked oil pressure at the rail, it'll go to 3000, then fall back to 24-2500 psi. The fuel bowl has a good spray of fuel at the drain valve.
I've replaced the cps with a good one, and new icp sensor.
Pulled the valve cover back off, and checked continuity across the injector plug, reads about 650 ohms.
With the glow plug controller unplugged, it'll fire on ether, and die.
The pats light and was are both doing what they should, and the fuel bowl heater is unplugged, and fuses all look good. Tried swapping relays around, no change.
Any ideas?

 

[Powerstroke Cowboy]

Do you have software to do a buzz test (koeo)

 

[DEEZUZ]

IDM.

Only certain people can hear the injectors while cranking, are they audible for you?

 

[dsberman94]

Pull the chip. Its definitely not firing for some reason if it’s seeing pressure and has fuel it should be firing. Double check idm fuse as well.

 

[psduser1]

I do not have any way to check software other than a scan Guage.
I cannot hear the injectors buzz by ear, but maybe I can get another ear on it tomorrow night.
The chip is out for a reburn.
The truck ran when it came in, but I do have another idm to swap in, hoping to avoid, that, lol.
Probably time to get forscan...

 

[DEEZUZ]

IDM swap is 3 minutes. You don't even unbolt it just pull harness and hang tester off the side.

 

[Powerstroke Cowboy]

It could be the IDM. Either way it easy to test.

The only thing changed in the equation was the Injectors? You tried to start before the icp and cps were changed right?

 

[psduser1]

Injectors were the only change.
I tried starting before swapping cps and idm..

 

[ToMang07]

If the batteries are bad enough and is not reading enough voltage that will stop them firing as well

Sent from my SM-F721U using Tapatalk

 

[psduser1]

New batteries, on the charger while cranking.

 

[Powerstroke Cowboy]

If swaping the IDM changes nothing it time to see if the injectors are even working.

Forscan is free to download on a PC. You just need a cable.

 

[Tiha]

Agree with checking injectors. Pull a valve cover and see if they are spitting oil while cranking.

Have you checked the HPOP reservoir to see if it has oil in it?

Don't know if it helps or not, but I manually filled the reservoir after injectors.
If it keeps emptying itself then you may have a large leak somewhere, damaged o-ring or bad check valve.

 

[psduser1]

3k on a manual gauge at the head while cranking, there's oil there.
I am not seeing oil dribble from the injectors while cranking, but I thought the solenoids had to be activated on the electrical side for the oil to come through the injector?

Is there an easier way to get to the idm than pulling the fender off? That's the only way I've ever done it, pita.

 

[Tiha]

Can you just unplug the IDM and plug the donor in next to it and try it?

Don't know on the ex. On my 95 it bolts on the fender well and is super easy to swap.

You did say 3k. So that is ok, you have oil. You are right no oil from injectors while cranking means they are not firing.

Is it the IPR sensor that tells them when to fire? Is it plugged in? maybe crank it with it unplugged? Not sure if that works on those years.

 

[psduser1]

Idm is between the inner and outer fender, I don't think I can get to it without pulling one or the other. Never had to, lol.
I have cranked with the icp sensor unplugged, no difference.
Ipr controls the amount of oil allowed to bypass the injectors, at the pump, and that appears to be working right. My 3k oil pressure is brief, than the pressure drops and stabilizes around 2500 psi.

 

[DEEZUZ]

The inner fender well is less than 10 bolts and sometimes I've taken out 3, folded the liner and accessed IDM.

Lots of regurgitation here.

The injectors are not firing. Bottom line. Easiest is to swap IDM if you proofed power to it is good.

 

[psduser1]

Tonight, that's the plan.

 

[Powerstroke Cowboy]

You have the oil pressure. The injectors are not firing. Either you got a bad set. It happens, or the IDM kicked the bucket between old and new injectors. Hard to imagine, but stranger things have happened.

 

[psduser1]

Well, idm swap didn't change anything.
What are the chances all eight injectors are bad, lol.
Pcm maybe? That's the only other change, pulling the chip, but I've never seen a pcm that only worked with the chip in.

 

[DEEZUZ]

And you have power to the IDM?