At my wits end.. Looking for any idea.

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PlayingWithTBI

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In researching my issue with it surging and throwing a 45 - O2 rich code, I'm leaning towards the ICM and going to replace it today. In essence what it's doing is sending pulses when it shouldn't and the computer thinks the engine is turning faster, so it throws more fuel at it. In your case, I'm thinking your computer is adding spark and fuel to it based on false RPM feedback? Here's a link to reasons for the 45 code.

http://www.misterfixit.com/code45.htm

Check your wires and connectors from your ICM to your PCM

http://www.gearhead-efi.com/gearhead-efi/wiring/427-2.gif

If it all checks out, IMO, I'd buy a good quality ICM like AC Delco or Delfi. This is what I ordered, even with shipping it was still way cheaper than Auto Zone!

https://www.summitracing.com/parts/ado-d1984a
 

Shane Dyer

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So I just did a compression test. All of the cylinders are well within spec. Lowest was 168. Highest was 185. As far as the bin file. None was selected. But the XDF file was 0D_TPV5_v250.xdf if that explains anything. The ECM is 7427
 

Shane Dyer

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In researching my issue with it surging and throwing a 45 - O2 rich code, I'm leaning towards the ICM and going to replace it today. In essence what it's doing is sending pulses when it shouldn't and the computer thinks the engine is turning faster, so it throws more fuel at it. In your case, I'm thinking your computer is adding spark and fuel to it based on false RPM feedback? Here's a link to reasons for the 45 code.

http://www.misterfixit.com/code45.htm

Check your wires and connectors from your ICM to your PCM

http://www.gearhead-efi.com/gearhead-efi/wiring/427-2.gif

If it all checks out, IMO, I'd buy a good quality ICM like AC Delco or Delfi. This is what I ordered, even with shipping it was still way cheaper than Auto Zone!

https://www.summitracing.com/parts/ado-d1984a
I had just responded when you replied. As far as the ICM. I have tried both the original and a new one with no difference. And to piggyback on what I posted yesterday, it never had an o2 code till I unplugged it when I was troubleshooting. It actually has a new o2 sensor in it that i changed roughly 3 months ago just to see if that would fix anything. I'll check the wiring next. Is there resistance values or anything I need to check with those?
 

Shane Dyer

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Welp. Checked a few things everything seemed fine. Figured I'd do new plugs wires, cap and rotor instead of the cheapo orilley stuff. Went to do a driving log and then at the end of the log the truck dies on me and wont start again. No idea why again. Figured I'd share the log here and see if anyone can tell me what's making it cut fuel?

https://drive.google.com/open?id=0B4aSwvgeSzm3YlB0a0l5MFNYbG00LVRrTk5ERUg5akFpVF80
 

PlayingWithTBI

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TBI, I tried to send my info by PM but the forum wont let me send images, so I hope im not intruding on Shanes thread.

I'm not sure, weren't you going to get an ALDL or take a trip to get a data log done? Try the suggestion earlier (on one of these threads by @Schurkey I think) take a timing light and advance it ~4*, see what happens.

Figured I'd share the log here and see if anyone can tell me what's making it cut fuel?
Sorry to hear about your truck dying on you. 1st thing to do is get a can of ether and spray it down the throat of the TB while cranking. If it fires temporarily, then it's fuel. If not it's spark.

What I can tell you, I changed the ICM (used MX-4 insulating compound) in my distributor (brand new Spectra Premium with only 3K miles), now it runs like a top - no more surging! What brand distributor/ICMs have you been playing with? Brand new parts have been know to be bad out of the box.

I'm gonna go fire up the Traeger and do some Tri-Tips (a west coast thing).
 

Shane Dyer

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I'm not sure, weren't you going to get an ALDL or take a trip to get a data log done? Try the suggestion earlier (on one of these threads by @Schurkey I think) take a timing light and advance it ~4*, see what happens.


Sorry to hear about your truck dying on you. 1st thing to do is get a can of ether and spray it down the throat of the TB while cranking. If it fires temporarily, then it's fuel. If not it's spark.

What I can tell you, I changed the ICM (used MX-4 insulating compound) in my distributor (brand new Spectra Premium with only 3K miles), now it runs like a top - no more surging! What brand distributor/ICMs have you been playing with? Brand new parts have been know to be bad out of the box.

I'm gonna go fire up the Traeger and do some Tri-Tips (a west coast thing).

So it definitely is fuel related. Had my dad look at the TBI while cranking and it wasn't spraying anything out of the injectors. Plugged in a new fuel pump relay, ran for about 30 seconds then died again. Checked the fuse. Fuse looks okay however dad removed it and plugged it back in and said it didn't seem that it was in there snug? But anyways got it back running and back home. Apparently from his knowledge it still has the original oil pressure switch? Not sure if that could be related as the gauge itself appears that it has oil pressure. But who knows if its finicky or not. As far as mine, my idle doesn't surge or anything of that nature, just the hard miss as if it's not getting enough fuel, then it gets to much, yadda yadda. But as far as ICM's go at first I had replaced it with one from the parts house. Dont remember the brand but made no difference. Used an original gm one from the donor truck. Same thing. New cap, new rotor button. New wires. And hell even threw new delco platinum plugs in it. No difference. (Obviously cause its fuel related at this point) not sure anymore. I've cursed at this thing so much I've ran out of words lol.
 

ShadowRejects

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sounds like similar issues as mine, when my ICM went poo-poo.
It was maybe 3 months old. I had just replaced with a Borg Warner (IIRC) and it was good for a few months. It was like clockwork, suddenly started dying on the way to work at the same 4-way stop every single day, sometimes started right back up, sometimes not.
It was like Russian Roulette. I eventually had enough when it left my truck sitting dead in the middle of a 4 lane road during 5 o'clock rush-hour traffic and I had to get out and push it up an incline (which failed miserably) and a cop miraculously pulled up and shut down 8 lanes of road to have a random Powerstroke owner tow me up to the gym parking lot. Oh man. Good times.

moral of the story, Don't always trust new parts.
 

Shane Dyer

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sounds like similar issues as mine, when my ICM went poo-poo.
It was maybe 3 months old. I had just replaced with a Borg Warner (IIRC) and it was good for a few months. It was like clockwork, suddenly started dying on the way to work at the same 4-way stop every single day, sometimes started right back up, sometimes not.
It was like Russian Roulette. I eventually had enough when it left my truck sitting dead in the middle of a 4 lane road during 5 o'clock rush-hour traffic and I had to get out and push it up an incline (which failed miserably) and a cop miraculously pulled up and shut down 8 lanes of road to have a random Powerstroke owner tow me up to the gym parking lot. Oh man. Good times.

moral of the story, Don't always trust new parts.

I'll try another ICM and see what happens.
 

PlayingWithTBI

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Make sure you use quality insulating compound like MX-4 under the module and good dielectric silicone on the connectors. Also I just read on another forum a member had a little hole burned in the rotor causing issues, don't know if that's your problem, just thought I'd throw it out there...
 

Schurkey

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So it definitely is fuel related. Had my dad look at the TBI while cranking and it wasn't spraying anything out of the injectors. Plugged in a new fuel pump relay, ran for about 30 seconds then died again. Checked the fuse. Fuse looks okay however dad removed it and plugged it back in and said it didn't seem that it was in there snug? But anyways got it back running and back home.
No fuel spray because the injectors aren't being triggered, or no fuel spray because there's no fuel pressure? Huge difference in diagnosis. Post #2 asked about fuel pressure.


Apparently from his knowledge it still has the original oil pressure switch? Not sure if that could be related as the gauge itself appears that it has oil pressure.
The gauge runs off of a different sensor--or at least a different set of contacts--than the fuel pump.

as far as ICM's go at first I had replaced it with one from the parts house. Dont remember the brand but made no difference. Used an original gm one from the donor truck. Same thing.

Repeated failures of the ignition module are often due to a partially-shorted ignition coil.

Ignition coils can be tested with an ohmmeter and proven to be DEFECTIVE. They CAN NOT be tested with an ohmmeter and proven to be GOOD.

The ohmmeter tests the coil with a miniscule voltage that does not stress the insulation. Actual operating conditions stress the insulation with thousands of volts. If the insulation is good enough to survive one volt, but not thirty thousand volts, the coil is defective but the ohmmeter will tell you it's OK.

If I test an ignition coil, I always include a spark test using a calibrated spark gap. If the ignition coil passes the ohmmeter test AND produces enough spark to jump the calibrated gap...then I'm satisfied that the coil is OK. If it fails either the ohmmeter test OR the spark-gap test, the coil is scrap.






The computer depends on the ignition module to send an "engine is turning" signal. Without that signal, the computer does not provide fuel. The module can fail in a way that you have spark, but no fuel.

NO spark, NO fuel can also be a pickup coil in addition to a faulty ignition module.
 
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