I'm running an AEM v1. I've been having issues with my tune fluctuating ever since I've had it installed and tuned 6 years ago. Last night I checked the grounds on the ECU's 13 pin connector.
The computer ground "E1" has no continuity to ground at all. "E01" and "E02" have ground continuity, but the chime on my voltmeter gets all quiet and garbled when I test them with the ignition turned to "on" (efi fuse is removed). I ran a ground from the body to the wire going to "E1" and now, not only does it have continuity to ground, but "E01" and "E02" now chime loudly on the voltmeter when checking ground continuity with the ignition key turned to "on". I installed the efi fuse and turned the key to "on". I hear the efans kick on and off and the fuel pump come on (pressure reads 43psi) which is all good, however, the engine will just crank and not even try to fire. Disconnected the new ran ground to "E1" and the engine fires right up. Thoughts? Since the car was initially tuned without this ground attached, could restoring it change the signal so much that my cold-start tune is not good now?
Btw, I also noticed that the IGDA wire for coil #2 is cut. I'm running sequential ignition, so they must have it set not to use that output, but still kinda weird since I don't even see a loose wire to connect it to. I'm dreading sorting this all out since if I do revert the wiring, the engine definitely won't run with the current tune. I'd hate to start from scratch, but I want it right. While I'm at it ,might just wire it up for sequential injection. Pretty sure that would definitely require a re-tune tho.
The computer ground "E1" has no continuity to ground at all. "E01" and "E02" have ground continuity, but the chime on my voltmeter gets all quiet and garbled when I test them with the ignition turned to "on" (efi fuse is removed). I ran a ground from the body to the wire going to "E1" and now, not only does it have continuity to ground, but "E01" and "E02" now chime loudly on the voltmeter when checking ground continuity with the ignition key turned to "on". I installed the efi fuse and turned the key to "on". I hear the efans kick on and off and the fuel pump come on (pressure reads 43psi) which is all good, however, the engine will just crank and not even try to fire. Disconnected the new ran ground to "E1" and the engine fires right up. Thoughts? Since the car was initially tuned without this ground attached, could restoring it change the signal so much that my cold-start tune is not good now?
Btw, I also noticed that the IGDA wire for coil #2 is cut. I'm running sequential ignition, so they must have it set not to use that output, but still kinda weird since I don't even see a loose wire to connect it to. I'm dreading sorting this all out since if I do revert the wiring, the engine definitely won't run with the current tune. I'd hate to start from scratch, but I want it right. While I'm at it ,might just wire it up for sequential injection. Pretty sure that would definitely require a re-tune tho.
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