Boyes50

Hi Guys,

Purchased a 2006 Cobalt SS 2.4L with the E67 PCM. I’ve stripped the interior out and in doing so, activated the VATS. I since turned it off, but have run into a new issue. I am tuning with EFILive.

Since removing the interior, when I gun the engine in first gear, it accelerates extremely slowly. I am told this is because the engine is in “Low Power Mode” or “Restricted Power Mode”.

Is there a way to tune the car through EFILive that will never allow the car to command this Mode? I’d hate to have it enter this Mode while I was racing also. I am not planning to mess with any other parameters as the PCM tuning is not permitted, I strictly want to ensure the car does not have issues like Low Power Mode or the VATS.

If anyone is familiar with this please let me know. Only code that is related to the engine currently present is P0013, which is the Camshaft Solenoid. I will have to unplug these for my racing class anyways as we must disable the VVT to make it fair for the older and less powerful cars.

Thank you in advance!

Slowbalt2000

iTrader: (1)

Does the dash say reduced engine power? If you dont have working vvt, the 2.4 is a dog until 4-5k rpm.

Sharkey

iTrader: (1)

there is sort of a catch 22 here, if you unplug the solenoid (like you need to for the class) the ecm is going to go into a reduced power mode because its detecting the problem. the best way to eliminate the vvt would be to zero out the tables for cam timing so it would put the cams at a fixed position, but your not allowed to tune the ecm. i cant think of any way to deactivate the variable cam timing without tuning and not setting codes. really this is the most unthought out rule ive heard in awhile, and its not just going to affect gm products, anything with vvt is going to have the same reaction when you starts trying to disable it without tuning the ecm. its something that should be brought up with the race director/tech department. i hate to say it but if they are going to be sticky on no ecm tuning and disable vvt, then you really have the wrong car, you need a cobalt with an l61 (2.2l up to 08).

you likely have figured out that your slow acceleration is likely caused by the cam solenoid code.

as far as efi live goes, they have next to no support for the cobalt community. they supported minimal stuff in the early days of the platform and as a result most people go with hp tuners as they have far more support for us. you will find quite a lot of stuff you can do with your ecm as the e67 is common on v8 applications, hence efi live put the work in on it. what im getting at is very few people here will be able to help you out as most dont know efi live software.

Boyes50

So:

Other people in this racing league are running the 2.4L Ecotec, and they are running with the solenoids unplugged. He says he unplugged the solenoids, and the car did not go into Engine Power Reduced Mode. The car won the championship last season. I also have not unplugged mine yet this season, this is an active code. I will be disconnecting them at some point before the season.

When the engine actually enters "Reduced Power Mode", what does the PCM/ECM change to limit the engines power? Does it revert to a different table? Does it remove timing or move to a different timing table? Again, EFI Live seems to be able to accomplish almost anything that HP Tuners can, so if someone has done this with HP then I can try and follow the steps to modify my tune the same.

Additionally, the car has absolutely no interior, and I have cut several "non-critical" wires from the interior harness. The gentleman who has the car that raced last season wonders if cutting a wire has caused this low power state.

Please let me know if anyone has any other suggestions. I can post up the other few codes as well. Additionally, the EPS does not work after cutting the interior harness, so could this have something to do with the issues? OBD2 functions as normal.

Boyes50

One other issue I just thought of. The car no longer cranks. After modifying some of the interior wires, Key On functioned by the start position would not crank over the car. I wired the Starter Solenoid individually with a push button on a separate harness.

Boyes50

Just took a data log of a WOT pull. With the throttle wide open, the throttle position maxes out at 40%. Timing increases, speed slowly increases, but the TPS, and I'm assuming the throttle body, do not open regardless of how much pedal is applied. Anyway to make this work correctly?

Slowbalt2000

iTrader: (1)

If you have multiple codes why arent you posting them? Obviously thats part of the problem... VVT being unplugged doesnt cause REP. The reason the throttle wont open more is because of REP. If you want help you need to tell the full story.

Boyes50

Codes Present Are:
P0013
P0532
P0650
U0121

Changes Are:
Interior Removed
Wiring Harness Cut Down
EPS No Longer Functions (Unsure Why)
Starter Trigger Wire Does Not Work (Won’t Crank with Key)
Rewired Direct Power to Starter Solenoid

Boyes50

Bump for solutions to remove Reduced Engine Power with Tuning (Would like it to never return, be simply "tuned out"

Have heard of some racecars running into issues with REP when the car runs hard over the course of a race, so removing it and ensuring it won't come back would be ideal!

Slowbalt2000

iTrader: (1)

You cant really remove REP, even erasing some codes that cause it can still trigger REP without the code even setting.

have you tried clearing the codes and seeing if it drives better?

Slowbalt2000

iTrader: (1)

Also about the power steering, did you plug the tan/grey connector into the fuse box? its the only connector that plugs directly into the fuse box.

Boyes50

I clear the codes, and they return. After clearing the codes, I used EFI Live to set them to not report, to see if that would prevent REP. Even with these codes turned off, the car remains in REP. If I can't remove REP, this is where my concern lies. With it still active, I'm assuming it can only be triggered at this point by some sort of wiring issue. I wish there was a way to simply take the max Throttle Position in REP from 40%, and move it to 100%.

Beyond the Throttle Blade Position being restricted, does REP modify any other parameters? Timing? Fuelling?

The power steering wiring is all correct and connected, except for the red wire which has ignition power. This red wire runs to the Interior Fuse Panel, and connects into it with another red wire. While this red wire is active and working, the red wire which ran out of that same port is live power, but has been cut. I'm unsure where this wire should go. Again, I actually don't care that its not working. I do not want or need EPS, as most of the racers in this class run with manual steering to avoid issues while racing.

Boyes50

Slowbalt2000, I followed a thread where you assisted with information regarding PCM Pinout. I have done some research and find schematics on this site for E37 and P12 controllers, but nothing for the E67 LE5 Cobalts. Do you know where I can find that? I'm wondering if it would actually be a LOT simpler to move to a stand-alone style harness, with a push button start and simple toggle switch, and avoid all the issues which are being caused by the BCM and interior harness.

Slowbalt2000

iTrader: (1)

I can get it for you but Im at work. Id have to do it when I got home one of these nights.

Boyes50

Want to close out this thread. A member named Steve who runs EFIHARNESS was able to provide me a tune which runs the car perfectly, without needing the BCM or Theft Issues. Steve was an absolute life saver, and got the vehicle up and running perfectly. To anyone needing help and guidance with Ecotec stuff, he is extremely knowledgeable!!!!

Slowbalt2000

iTrader: (1)

Glad you got it worked out. EFIHARNESS is a good resource to have.