08 HHR SS tuning issues, won't idle or run

[RiordanII]

I just installed an off road zzp downpipe, full 3'' zzp exhaust, 3 bar map sensors, zzp intercooler and charge pipes. Using my HP Tuner, I flashed my ecm using the starting tune copied from cobaltssoverbooster (thank you!). After the tune was flashed into the computer, The car started and ran, but the anti theft light was on. I drove it a couple of miles, shut it off, and restarted it because it wasn't making any boost. Once I started it, the CEL was on. I drove it back home, shut it off and checked the DTC's. The only one I got was for the MAF airflow not being correct. I checked the MAF connection, and it was good. I cleared the DTC's, turned the key off and then tried to start the car. I would crank and start but just as soon as it started to idle down, it would die. I've double checked the tune to make sure I didn't overlook anything. I could get it to run if I feathered the throttle, but it absolutely won't idle. I took a log of it running while I was feathering the throttle and I took a picture of the last DTC screen that I read. Any help would be greatly appreciated.

[califcarm]

I just installed an off road zzp downpipe, full 3'' zzp exhaust, 3 bar map sensors, zzp intercooler and charge pipes. Using my HP Tuner, I flashed my ecm using the starting tune copied from cobaltssoverbooster (thank you!). After the tune was flashed into the computer, The car started and ran, but the anti theft light was on. I drove it a couple of miles, shut it off, and restarted it because it wasn't making any boost. Once I started it, the CEL was on. I drove it back home, shut it off and checked the DTC's. The only one I got was for the MAF airflow not being correct. I checked the MAF connection, and it was good. I cleared the DTC's, turned the key off and then tried to start the car. I would crank and start but just as soon as it started to idle down, it would die. I've double checked the tune to make sure I didn't overlook anything. I could get it to run if I feathered the throttle, but it absolutely won't idle. I took a log of it running while I was feathering the throttle and I took a picture of the last DTC screen that I read. Any help would be greatly appreciated.

I think you are supposed to copy/paste the table values for where they are different, but not flash his entire tune as it can cause problems. So open your original tune, use his as a "compare" file, and copy/paste his values where ever they are different than yours.

[RiordanII]

that's what I did. Sorry, I should be more concise in my explanation. I've compared every aspect of the tune using the compare feature and they're identical. I've since rechecked all the electrical connections, vacuum lines and charge pipe connections, and have found nothing.

[cobaltssoverbooster]

it does not sound like you copied and pasted. the only reason the theft light comes on is due to a direct flash from another vin. the theft light triggers because the vin doesn't match from the bcm to ecu. do a read on the ecu and compare the vin to the chassis vin in the window or on the door sticker.

some vin compare issues let the vehicle start but die shortly after and others straight up shut the pump off only allowing the starter to rotate. In the first case if the engine runs it will die when it is rev'd or put in gear as the ecu see's that as intent to drive away. since the vin doesnt agree in with the bcm the bcm cuts the fuel pump.

it would be wise to do a read and verify an accident wasnt made.

If the vin is good there are ecu's from different years which run the axis of the maf sensor in opposite directions. some start at 0 hz on the left and go to say 500k hz on the right and others go the opposite 500k hz on the left and 0 hz on the right. when transfering data the axis must be double checked to prevent issues from axis swap in Model Year (MY) ecu updates.

[RiordanII]

I did read my stock file and transferred the values from the tune you provided. I just went through for the 4th time checking that I hadn't missed anything. I pulled a base file this morning before I flashed the computer incase this happened.

[RiordanII]

just checked the MAF frequency axis, and they're identical running left to right.

[cobaltssoverbooster]

perform another read entire. when you open that file, it shouldn't ask you to pay for credits. If you do a read entire after making the adjustments and it asks for credits then you mistook the files and flashed mine directly in. you will either have to pay a dealer to reflash a stock file in or i have heard you can pay the credits to unlock my files vin which would then allow you to flash.

alternately you could try and flash your stock file in as a write entire and if it doesnt allow the flash process to complete then you have the wrong file loaded into the computer.

[RiordanII]

I did a full read this morning before I flashed the tuned file. Should I copy and paste into that file, save it as a different file, and try it again? By the way, a facebook friend that also does tuning advised me to unplug the MAF sensor and then start the car. Once it warmed up, he told me to plug the MAF back in. I got the car home, but it ran like crap....lol...

[cobaltssoverbooster]

from your last message i am getting that you did a full read and were able to flash the stock file back in as a "write entire" function.

If that's where you got to then its time to start new filing. start by deleting your modified file that doesn't run properly. it isn't unheard of for a file to get corrupted during flash its possible it happened to you. Generally speaking there are only 2 reasons the passlock light comes on in the dash: 1) the key isnt the right one or doesn't have a chip in it and the bcm is having issues verifying the electronic access codes. 2) the vin numbers don't match between ecu and bcm. If both of these are good then the passlock is another issue for which if the ecu is reset to stock and the passlock deactivates then i would chock that up to flash file corruption.
To prevent overloading the flash try performing multiple writes to see if its file corruption or ecu setting errors. to do this correctly make a new file based on your stock one by using the "save as" function. Try making multiple files in which you try uploading new data for a specific section such as: File 1) Tqm changes only. File 2) Reset fueling to base tune-able File 3) standardize ignition ..... etc. Once you get all of the changes in without issues you can start tuning each section individually as you wish. When you write to the ecu don't use write entire....use write calibration only. Its faster and it prevents errors in flash.

Make sure your laptop is charged and the battery is fully charged before flashing. Any wavering voltage can cause issues during the flash process so don't go opening doors or using vehicle functions while the software is writing to the ecu. CAN activity can also cause interference which is why vehicle systems should be left alone.

double check your axis when copying over. If you use my cobalt files that i usually have uploaded then those are '08 files, i don't think you will have axis transfer issues.

[RiordanII]

I found my issue today....I feel like an idiot. I was going over all the electrical connections and vacuum lines for the third time and found nothing. Then I thought why not double check all the intercooler boots just to make sure....guess what? I had a boot blown completely off. I get it back on, clear the DTC's, and now it's running perfectly. I'm going to try the modified tune again tomorrow. Thank you for all the advice, I'm sorry it was something so stupid..