E38 Standalone problems

[GAMEOVER]

Standalone harness & ECM(E38)
I just flashed a 2008 1500 L76 6.0ltr 4L70E 0S(12617631) into a E38 that originally came in a 2008 3500HD Silverado LY6 6.0ltr 6L90E OS(12622142)...Everything is fine at start-up....Motor turns on, revs but when I go to move the vehicle, it goes into some sort of Limp mode and accelerator pedal will not work and motor just idle's no matter what I do!!! I check DTC's and it shows dtc's for cooling fan & Malfunction indicator light(easy fix)....But other times it will show **Camshaft Position Sensor BANK1 & BANK2 fault***

Any ideas? Maybe I should have used a E38 from the same type of 1500 Silverado?:shock::shock:

[ScarabEpic22]

I think you're gonna get into the different platform options with different OSs. I would use a Tech II to flash the proper OS into the ECM, Im betting the different transmissions are causing your issues. It sucks we cant use EFILive to full flash E38/E67s from different platforms, but thats how it works.

[GAMEOVER]

So even though it's same year it's still not gonna work?

[GAMEOVER]

I just re-checked all connections & pin location's and everything is where it's supposed to be...:D

[ScarabEpic22]

I doubt it, year is just part of the factors. If it was from an 08 1500 but different OS #, you'd have a shot. The differences between the 1500 and 2500HD are subtle, but each OS is distinctly tied into whatever transmission options are offered. The 2500 has the 6L90E, the 1500 has the 4L70E. Yes the TCM handles the actual trans shifting, but the comm protocols between the ECM and TCM are likely different and this is where your issue is.

You either are going to have to Tech II a stock 1500 OS or use a different transmission. Since the engine runs fine and lets you rev it, Im betting its not accelerator pedal related but moreso the ECM<->TCM comms because the issue manifests itself when you shift it.

[GAMEOVER]

I'm also using a non-electronic 700-R4

[turbo_bu]

Any chance you have a manual transmission flash file you could use? That would eliminate the ECM from looking for the TCM stuff. It might be enough to not need a Tech II to do a full GM type flash.

[schwoch1]

Any chance you have a manual transmission flash file you could use? That would eliminate the ECM from looking for the TCM stuff. It might be enough to not need a Tech II to do a full GM type flash.
I was just going to say the same thing, without any neutral safety, etc... computer goes into F*&k you mode..

Mike

[GAMEOVER]

Trying to find a ECM for a 2008 V-Max isn't easy...:(

[GAMEOVER]

Any chance you have a manual transmission flash file you could use? That would eliminate the ECM from looking for the TCM stuff. It might be enough to not need a Tech II to do a full GM type flash.

All I have is automatic files from 2008 1500 Silverado's

[Taz]

Hello GameOver,

Take a look at the linked thread below ... same type of conversion as yours ... have never done this ... not sure if it will help or not.

http://forum.efilive.com/showthread.php?16140-Ve-commodore-powerglide-conversion

Good luck ...


Regards,
Taz

[Taz]

The only manual transmission tune I can think of for that OS (12617631) is from a 2008 Corvette. Given that you are working on a stand-a-lone type setup, you could try swaping in the system segment from a manual transmission equipped Corvette engine tune, into your truck engine tune. Not sure how (or if) this would effect TB / APP function in your truck based tune.


Regards,
Taz

[ScarabEpic22]

Didnt realize it wasnt paired to the stock 4L70E...this makes things interesting.

Switching to a Vette tune probably isnt a good idea because Im betting the pedal assembly (maybe throttle body too) is/are different and the pinouts might very well be too.

Try bridging those wires as stated in the other thread. Maybe that will let you drive it, then you can kill whatever lingering DTCs are there.

[GAMEOVER]

I have a OBDII port... Why would I need to bridge those wires together? I'm not using a stock electronic transmission

[ScarabEpic22]

Exactly, because you arent running a TCM you need to have the CANBUS wires bridged so there isnt an interrupt in the circuit. There is a good chance because the ECM is seeing a break in the CAN comms, its freaking out.

[GAMEOVER]

But wouldn't i get a DTC for that?

[GAMEOVER]

Where would I get the wires from? The ecm has it's own Canbus wires, I'm using them for the OBD2 port.....I'm not following what you guys are saying....:shock:

[ScarabEpic22]

OK so its a standalone harness, what did you do with the CAN wires that run between the ECM and TCM? Anything? Did they exist in the original harness, or is this a custom one-off harness?

It seems if there is a break in the GM CAN wires the ECM freaks out, if you have a dangling CAN wire that is supposed to go to a TCM then it needs to be bridged back to the ECM.

[GAMEOVER]

It's a custom harness...I've done about 11-12 E38 custom harness's that are being used with TH350's, TH400's and 700-R4 transmission's but this is the only one that I didn't use the stock ECM & Pedal off of the original donor vehicle... I used a E38 ECM & Pedal from a 2008 HD3500 that had a 6.0 gas motor & 6L90E transmission! Which had a different OS & Service number...

All the other harness's & ECM's a running fine to date...Same pinout, wire, connector's e.t.c.

[ScarabEpic22]

Alright then you're going to need to use a Tech II and flash the correct OS in. Since EFILive cannot truly full flash Gen IV ECMs, there is lingering information from the HD that is probably causing your problems. I dont know if there is anything else you can do besides that right now, or flash the HD stuff back in and use HD pedal, tb, etc.

[GAMEOVER]

Yeah, I'm hoping it's just that... It's been kicking my butte, I actually lost sleep over it last night...:D

[ScarabEpic22]

Thats never fun man, let us know what happens when you've tried that.

[GAMEOVER]

I found a stock 2008 L76 E38 Computer disabled Vats/Applied Vats Patch e.t.c..... and gave it a mild tune...Well so far so good!!! Customer has been driving it for 30 minutes with No limp mode reported! I told him to keep driving it & check for DTC's....:D

EDIT: I just checked the E38 compatabilty chart & both the Service #'s & OS's are compatible under the chart....I'm thinking the 2008 E38 with the OS with HD3500 w/6L90E ECM was bad from the begining...:bad:

[joecar]

Good job :cheers:

[ScarabEpic22]

Nice, the service numbers just mean the ECM is the same part number...not the same OS/cal from what Ive seen. Be interesting to see if you cant flash the HD E38 with the right tune, kill VATS and see if it works. Then we'd know for sure if the ECM is messed or if there is hidden stuff that's messing with it.