Alrighty, so HP Tuner noob here. I had my transmission rebuilt and got HP Tuners so that I could tune the transmission. Well I think I got a bit ahead of myself and tried to tune out VATS (my security light was constantly on). I've had my PCM tuned by someone else in the past and they flashed it with no issues. Now my PCM is showing P0602.

What I did was before the car was sent off to the transmission shop, I saved the current tune into my computer. I then copied that file and made changes to it related to the shift points, pressure, fan temp, etc., nothing that would not make the car start. I think what happened is I set my VATS from PWM to None.

Now the car will turn over but won't start. I've tried reverting to the old file with a Write Calibration or Write Entire but with no luck.

So my question is.... did I fry my PCM or did I just only disable a portion of VATS and there's some hope to get it to start? I deff won't be screwing with VATS anymore. Could I disable P0602 in engine diagnostics and could there possibly be more codes there related to VATS?

Other questions:
1) How do I know it's the PCM and not the BCM?
2) If I get a new PCM, do I need to flash my VIN or do I just leave it as is? *Update* - Figured out the VIN is changed in Scanner, done.
3) A buddy has another 98 PCM which was converted to M6, can I just do a write entire with my stock file and get it back to 4L60E?

I appreciate the help in advance, take it easy on me. I know I may have screwed up but I'm in it to learn and of course there's a cost associated with screwing **** up lol.



*Files attached*
"98_SS_PreStall.hpt" - This is the file that started and ran before I flashed it.
"98_SS_PostStallWontStart.hpt" - This is the file I flashed which caused it not to start (however I did turn VATS back to PWM) in this file but it was set to None when I flashed it.

 

None is the correct setting. Should have no issue disabling it. I think you have another issue. The computer only looks for the bcm OK if the setting is turned on. If it's set to off the motor can run with no bcm.

 

I drove it 50 miles and then parked it, flashed it, then it wouldn't start, even after reverting back to the tune file. I think the PCM may be fried.

 

I tried to cover the chip in the key which I'd assume if it's set to none, it wouldn't be looking for anyways. I've heard horror stories about tuning 98 PCMs and some of them just bricking for no reason. Maybe someone knows what could be wrong.

 

I think I figured out the issue. It looks like there was probably an OS upgrade I wasn't aware of and they are saying since I did a calibration flash like this guy I fried it.

https://www.hptuners.com/forum/showthread.php?53589-Help-car-won-t-start-after-flash

 

If it's an LS1A style pcm any time you flash it your playing with fire. They only used them for a couple of years, I have heard of a lot of people that have had issues with these making even basic changes.

 

Yea so I've heard. I picked up a PCM from a friend which is a 98, it has been tuned before but it was converted from A4 to M6. I am under the impression I can flash my stock file to it as a full write to get it to convert but the VIN may not change since HPTuners removed the ability to do that manually.

I thought about just going to buy another PCM which would have a warranty, but they all say "flash unit" and I'm not sure if it comes with no OS and I'm supposed to be able to flash it from HP Tuners or if that's an impossible task with this tuner. I guess I'll see but fingers crossed on this one.

My PCM has taken a tune several times, so has the one I just picked up, it was just a mistake on my end, I wasn't aware the OS changed, must've accidentally did that but you'd think they'd make a way to completely erase it and fix it, oh well.

 

Okay. Got a hold of another 98 PCM my friend had that was converted to work with a M6. I updated the parameters and added values back to the transmission tables, installed it, flashed it, and the car fired up. I gotta go back and see if there are any other tables that were cleared that I may have missed. I also don't know if there are any fuel tables he may have changed because the car had quite a few modifications to it and I don't want it to cause my car to run rough. Good news is it is alive at least!

Does anyone know if the auto part store PCM's that are "flash units" come with an OS installed and can be overwritten with HP Tuners?

Also can the VIN be updated with a Write Entire?

 

Noob in training here. Sorry I figured out the VIN changes occur in the Scanner, not Editor. I had just assumed all "edits" were done in the Editor.