ZO6 Computer Won't Reflash

[Stoichiometric]

I have been tuning my 2002 ZO6 (440CI Fast 90/LS2TB, 232/240 117 cam) for a while and have everything dialed except for the idle. It idled smoothly at 850rpm , but would hang throttle 15% opening 1500 rpm, in gear and out of gear until I come to a stop (0 mph) for about four or five seconds then it drops to 7% opening and 850 rpm. I tried a number of suggestions from this forum an I found two things that were different for me. I first tried lowering the ETC throttle Area conversion B4349 from the stock .025 to .015 as was suggested and the idle surged severely from 300 rpm to 1400 rpm occasionally dying. I then kept raising this above my factory setting of .025 and it got better so I am now at .05 (B4349), no more surge. Now I have the hanging throttle, so I lowered my ETC Max Position for Idle B2713 from stock 18.3 to 9 and the hanging rpm was greatly reduced to about 1100 rpm, I then thought I was on the right track so I lowered it to 7, and everything was perfect. I then came to a stop sign turned off the motor and tried to restart it which sometimes would bring back the problem and it would not restart. I could hear that the fuel pump would not turn on and I had error messages such as coolant temp 270, reduced power, ect. I tried to reflash a previous tune and I could not establish communication with the PCM, I did a test and it said communication error no recovery options during the attemps at reflash. I am currently downloading the latest V1 software and will try a reflash with that. Is my PCM dead (needing replacement) or can I recover it? Any comments on what I did and need to do are appreciated.

[VYSSLS1]

does the scanner work, eg can u connect and scan, or does that play up.

[GMPX]

Where you doing a calibration reflash or a full flash?

Cheers,
Ross

[wait4me]

Send me the pcm if you can, Ill look at it and replace it for free. Not sure what happened? did the laptop get a bad usb connection? Where you using a power inverter? Does the cable work in another car?

[wait4me]

One more question. What version of software where you using?

[Stoichiometric]

All, Thanks for the replys, there was a flash memory failure indication whenever I tried to scan or reflash. I am usuing the latest download 7.3. I ended up replacing the PCM ($149 from Ken Fitchner Chevrolet) and downloaded my original stock operating system into it and everything linked up and is working fine. I appreciate the offer for a free fix wait4me, I had to send my froze up PCM back for a core deposit refund.
I'm pretty sure that when I messed with the ETC Max Position for Idle (B2713) after reading the warnings is where things went bad. The car ran fine after my reflash, when I turned it off and tried to restart is when the flash memory failure occured. Oh well, I've learned my lesson not to mess with the parameters they say not to mess with.
I currently have the tune very close without an altered (B2713) so I'm progressing.

Thanks again.

[wait4me]

Glad you figured it out!