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GMPP LS7 tune problems

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Old Jun 25, 2009 | 06:29 PM
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Default GMPP LS7 tune problems

I am working with a local tuner trying to tune a GTM. It has a LS7 with a decent size cam installed. The computer is manufactured by GMPP. Using HP tuners we can not seem to make any changes to the computer. We have been in contact with HP tuners, they are trying to help, but they really dont know what is going on either. We can extract, write and scan, but no matter what changes we make it doesn't change the way the car runs. We have changed the idle everywhere from 100 to 2000 rpms, changed the settings so that it only runs on open loop, and no change.

The car seems to have a low idle, and when you get on the throttle and back off it wants to die. It also runs pig rich throughout the rpm band.

Anyone have any ideas? Thanks for any help
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Old Jun 25, 2009 | 06:45 PM
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bad iac?
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Old Jun 25, 2009 | 08:41 PM
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Originally Posted by 99345hp
I am working with a local tuner trying to tune a GTM. It has a LS7 with a decent size cam installed. The computer is manufactured by GMPP. Using HP tuners we can not seem to make any changes to the computer. We have been in contact with HP tuners, they are trying to help, but they really dont know what is going on either. We can extract, write and scan, but no matter what changes we make it doesn't change the way the car runs. We have changed the idle everywhere from 100 to 2000 rpms, changed the settings so that it only runs on open loop, and no change.

The car seems to have a low idle, and when you get on the throttle and back off it wants to die. It also runs pig rich throughout the rpm band.

Anyone have any ideas? Thanks for any help
Is it ETC, or cable throttle? When you say you programmed it for open loop, but no change, did it at least stay in open loop? Are any changes happening? Need more specific info. A run log and tune would help too.
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Old Jun 26, 2009 | 06:35 AM
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You say that you can "We can extract, write and scan" but did you flash the changes back in to computer?

Normally you would read entire, then edit, then save the new file and then write calibration files to the ECU.

HP doesn't edit in real time so you need to write the changes to the ECU.

The crate engine ECU's seem to be on "safe" side.

Robin
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Old Jun 26, 2009 | 06:11 PM
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Originally Posted by Robin L
You say that you can "We can extract, write and scan" but did you flash the changes back in to computer?

Normally you would read entire, then edit, then save the new file and then write calibration files to the ECU.

HP doesn't edit in real time so you need to write the changes to the ECU.

The crate engine ECU's seem to be on "safe" side.

Robin
god i sure hope hes smart enough to realize this
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Old Jun 26, 2009 | 06:22 PM
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Originally Posted by Robin L
You say that you can "We can extract, write and scan" but did you flash the changes back in to computer?

Normally you would read entire, then edit, then save the new file and then write calibration files to the ECU.

HP doesn't edit in real time so you need to write the changes to the ECU.

The crate engine ECU's seem to be on "safe" side.

Robin
This is my first experience with tuning, but I think we are doing it right.

We have tried write entire and write calibration both. Neither one make any changes to the way the car runs. It is a electronic controlled throttle, so no IAC. It also seems to run really really rich.

Today we copied alot of tables from a stock CTS-V, but no change to the way the car runs. We also tried lowering the Rev limit to 2500, but it would still rev up past 4000 sitting in neutral. The customer support at HP tuners doens't seem to know why we arn't getting any changes in the running of the car either.
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Old Jun 26, 2009 | 07:10 PM
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LOL. maybe you locked it by accident when you full flashed.
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Old Jun 26, 2009 | 08:03 PM
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Sorry I had to ask.

Robin
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Old Jun 26, 2009 | 08:05 PM
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Originally Posted by 3fingas
LOL. maybe you locked it by accident when you full flashed.
why is it so funny? Isn't this forum for people to solve problems and ask questions?

how would we know if that happend?

I forgot to add. If we make changes and flash them to the computer, restart HP Tuners and do a read entire the changes are there. Why would it say the changes are made, but not change the way the car is running?
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Old Jun 26, 2009 | 08:19 PM
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Make sure you WBO2 is working/configured properly.
I had a sensor burn out on me and it read lean at WOT,
after adding fuel to the VE table the WBO2 still showed lean.
I thought something was wrong with the tune but it was the WBO2 the whole time.
LOL. maybe you locked it by accident when you full flashed.
It would unlock when reflashing, he could not "lock himself out" with the same cable.
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Old Jun 26, 2009 | 09:46 PM
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Originally Posted by shoemike
Make sure you WBO2 is working/configured properly.
I had a sensor burn out on me and it read lean at WOT,
after adding fuel to the VE table the WBO2 still showed lean.
I thought something was wrong with the tune but it was the WBO2 the whole time.
When I say its running rich, I mean there is a good amount of black smoke coming out of the exhaust. It also smells really rich and the plugs are black as night.

I did find out one thing today though. If I disconnect the MAF sensor it will have a constant 1 foot blue flame coming out the exhaust. Well its coming out of one set of exhaust pipes. It has 3 different sets of exhaust on the same car. (customers design)
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Old Jun 27, 2009 | 12:08 AM
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Originally Posted by 99345hp
why is it so funny? Isn't this forum for people to solve problems and ask questions?

how would we know if that happend?
I apologize, didnt mean it that way. If you would attach the file, a few more eyes could help. If you can, you may consider starting over and full flash the original file. Normally you would read this file and save it, edit the cal and "save as". Making incremental changes and saving them as well, hell by the time you dial it in you could have 10 files.

Since you copied tables from another unrelated file, you might be eight steps in the wrong direction and two in the right.

Originally Posted by shoemike
It would unlock when reflashing, he could not "lock himself out" with the same cable.
Correct, I thought he said it wasnt able to re flash or wasnt able to flash an edited cal.
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Old Jun 27, 2009 | 06:58 PM
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Here is a thread he has going in the HPtuners forum. This link has all the files you are requesting.

http://www.hptuners.com/forum/showth...931#post175931
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Old Jun 29, 2009 | 05:42 PM
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did anyone take a look at the tune and logs off the other thread?
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