Unable to read 09 Cobalt SS TC PCM with HP Tuners

[GeforceXtreme]

Hey Guys.

Hopefully someone can shed some light on the issue I am having. A month ago I bought a completely stock 2009 Cobalt SS TC Sedan. I am the 2nd owner and the previous owner was an older man that bought the car brand new and unloaded it once he passed 100K on the car in just 3 years. He strictly used this for company travel and besides normal maintenance nothing was done to the car (from what I was told and saw).

I have owned an HP tuner for years and well I wanted to license my Cobalt and start doing a basic tune to it. Well I went to link up with my car and I am getting a read VCM error 0. The guy at HP it saying it could be because it was previously tuned and locked?

I know others have reported having issues trying to get HP tuners to read the PCM’s. Some give suggestions of doing a series of things before reading but no luck for me. I may try pulling the radio fuse being in another car I tuned years ago the Onstar would cause HP tuners not to be able to read being the BUS was busy. I will try this on mine I guess.

However HP tuners said this: Read failed at location 0 means theres an issue with the pcm, not comms. It means right at the beginning of the read it failed, it got through comms without issue. So that would mean me pulling the radio fuse won't do anything.

I tried changing from cruse to non-cruse mod to see if maybe it did have one of those “select” a tune but didn’t notice any difference.

I did contact Trifecta to find out if they ever tuned my car.

Below is the information I pulled from my HP tuner when connected to my car.

Type: Chevy Cobalt (I4) 2009, E77
VCM ID: 86YRUD482640202
ECM OS ID: 12629314 [Editor] [Scanner] E77
ECM Calibration IDs: 12629314 12633168 12629325 12629326
ECM Seed: 0

[Iam Broke]

A Turbo LNF uses an E69 ECU as I recall, but I am fading fast.

Perhaps your HPT software is old? You can D/L 2.24 now.

A TF tune will read but fail at the end of the read, not the beginning.

Backyard Turbo (Nick) was doing weird things in your area tuning LNF's and locking them. Perhaps that's why it thinks it's an E77 ECU. IDK. He faded off the face of the planet a while ago.

What boost do you see WOT?

Not doubting you but it's a turbo LNF right?

It's been a while since I looked at an LNF but I'm sure one of the current guru's will correct any errors I made in the post.

[GeforceXtreme]

A Turbo LNF uses an E69 ECU as I recall, but I am fading fast.

Perhaps your HPT software is old? You can D/L 2.24 now.

A TF tune will read but fail at the end of the read, not the beginning.

Backyard Turbo (Nick) was doing weird things in your area tuning LNF's and locking them. Perhaps that's why it thinks it's an E77 ECU. IDK. He faded off the face of the planet a while ago.

What boost do you see WOT?

Not doubting you but it's a turbo LNF right?

It's been a while since I looked at an LNF but I'm sure one of the current guru's will correct any errors I made in the post.

Yeah My car is a 2009 Cobalt SS TC Sedan. Not sure if the sedan/coupe has anything to do with the PCM # being different then what you say? Everyone else I showed this too didn't say anything about the PCM being wrong.

When I went to scan yesterday this was on a laptop that never had HP tuners on it. Installed 2.24 and latest drivers. I even had the issue when i tried my older laptop with 2.23 beta.

Trifecta confirmed they have never touched this car. I have tried going WOT with/without cruise on to see if it had one of those select a tunes but same performance no matter what. They did say to try putting on Comp mode and traction off to see if that does anything then.

Car boosts around 15 or less PSI at WOT. To me it seems to act like a bone stock car without a tune. Who's to say it was tuned and put back to stock but being age/status of the previous owner.. I really don't think he touched anything with the car besides drive to/from work.

HP tuners is looking over my debug file to see if its an issue.

[Iam Broke]

I really suspect someone tuned it and returned it to stock in a non standard way. Might want to talk to your GM dealer or shop and get it flashed stock with a TechII.

Not at home to pull up an LNF file, I'll look for one though to check the ECU numbers, ect.

I found one of my own '08 files on a flash drive here, E77 is correct. Someone with an '09 can verify the correct cal #'s.

[Bill@HPTuners]

We just have it mislabeled in the editor, been that way for a LONG time now, low priority to fix(might not ever fix it as I'm not sure if it would break something by doing so). Really doesn't have anything to do with his issues though. I too believe his pcm was likely previously modified, maybe returned to stock, no way to tell though if you cannot read it.

[Area47]

A Turbo LNF uses an E69 ECU as I recall, but I am fading fast.

Perhaps your HPT software is old? You can D/L 2.24 now.

A TF tune will read but fail at the end of the read, not the beginning.

Backyard Turbo (Nick) was doing weird things in your area tuning LNF's and locking them. Perhaps that's why it thinks it's an E77 ECU. IDK. He faded off the face of the planet a while ago.

What boost do you see WOT?

Not doubting you but it's a turbo LNF right?

It's been a while since I looked at an LNF but I'm sure one of the current guru's will correct any errors I made in the post.

he's in jail. narcotics bust.

[Iam Broke]

oops.

[Bill@HPTuners]

Just to follow up, the pcm WAS in fact previously tuned by someone else, he found some sort of competition switch that switched boost levels.

[Iam Broke]

Prob a tf/hpt layer tune ala BYT. I wonder if it was Gimpster's red sedan. lol.

Thanks for the info Bill.