Another 7730 issue
#1
Another 7730 issue
I have a 91 3.1 V6 with the 7730 ECU that will only run at idle and hesitates/misses under any throttle. The check engine light is on all the time and does not blink when you turn the car on. Also when grounding the ALDL pin it still stays on solid. No code 12 flash or any other signs of life. I'm thinking the ECU is fried. Any thoughts?
#3
Re: Another 7730 issue
Thanks. So what would cause the ECM to fail besides old age? I've heard some say starting with a bad battery or something like that? I'm curious so that I can better take care of the system once repaired.
#4
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Re: Another 7730 issue
RBob.
#5
Re: Another 7730 issue
Hey folks I tried a new ECM thanks to Brian but no luck and no change in performance. Engine starts and idles fine but has a hesitation and maybe a miss under load or acceleration. Check Engine Light (CEL) is on all the time. Even with engine off and ALDL pin grounded the CEL stays on constantly and won't even blink the code 12. I guess I'll need to check all the wiring for continuity but anybody have ideas please share.
Thanks
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#8
Re: Another 7730 issue
Yes, that is the line I am grounding but the light stays on and does not blink.
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Re: Another 7730 issue
Since the CEL doesn't blink at key-on, engine-off, the ECM isn't running from the PROM. It is in limp mode.
RBob.
RBob.
Last edited by RBob; 06-28-2018 at 03:18 PM. Reason: spelling
#10
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Re: Another 7730 issue
Rbob, wouldn’t he have a code 41 or 51 ? Or does that not happen if he has a bit flip .
I think he mentioned to me he’s using a Piggyback adapter. So maybe it has a bad solder joint.
I think he mentioned to me he’s using a Piggyback adapter. So maybe it has a bad solder joint.
Last edited by Tuned Performance; 06-28-2018 at 01:10 PM. Reason: More useless data
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Re: Another 7730 issue
Depends, if the bit flip was anywhere except the power up initialize code, it would be a simple checksum error. This causes a rapidly flickering CEL and code 51.
RBob.
RBob.
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