limp 7730

[Shannen Durphey]

Does this happen with the scan tool connected?  Without?  I've had troubles leaving
the scan tool connected and alive through a shutdown/restart sequence.  For Y body
cars the problems include false check engine light, locked up scna tool
communications, inability of the bcm to communicate with other modules, loss of
digital dash data, false illumination of various dash warning lights, no start,
poor running, false VATS or other trouble codes.  All cases involve an aftermarket
scantool, that is, not a Tech 1.

I have had good luck with disconnecting the scan tool and shutting the key off for
15-20 seconds before restarting the car.

Shannen

Fisystems at aol.com wrote:
> 
> Strange problem for me but, maybe you guys have had or heard of this. I'm
> running a 7730 on a L98 TPI race engine. Dyno numbers 510tq 465 hp. The
> problem is the thing will go into limp mode every time I shut it off and try
> to restart it. When it restarts it's in the limp mode. No communication with
> scanner and base timing with static pulse width at the injectors. It will
> stay that way until I disconnect the battery and reconnect it. I can then
> start it and it will run fine, no codes, close loop and good power. I have
> checked the power wires and grounds and all seems to be in order. I moved the
> battery power to switched power so that I can shut it off and than restart it
> without having to disconnect and reconnect it. With it wired that way if the
> engine stalls and the power switch is still on, I can watch the scanner lose
> communication after about three seconds. If I just hit the start button
> without turning the power off and back on it's in the limp mode. Any ideas?
> 
> Thanks
> 
> Ken
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