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just thought that an intermittent short to power might do it, as well... as close to the starter wiring as stuff is around there... i dunno.
 

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Discussion Starter #22
I 100% agree with your synopsis. Haven't had a chance to get back out there and do more testing.
 

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Discussion Starter #23
Got a small update. I had my wife turn the engine by hand while I kept eyes on the reluctor through the sensor aperture the entire time and did not see any anywhere that was bent. Then I back pinned the wiring at the sensor to see what kind of output I was getting on the signal wire. Still turning the engine by hand I get a clean on/off on the multi-meter. Off is dead 0V; on shows 10.2V-10.3V every tooth. That figure surprised me a bit as I would've thought it would be a 5V signal or the 11.5V I see on the positive reference wire. I'm having a hell of a time finding a spec for this signal online, but I'll search my manual and see if it says anything about it.
 

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That figure surprised me a bit as I would've thought it would be a 5V signal or the 11.5V I see on the positive reference wire. I'm having a hell of a time finding a spec for this signal online, but I'll search my manual and see if it says anything about it.
reference voltage seems on the low side but all depends on what else is on when testing, (lights, radio, blower motor, etc. etc) a 9vdc reference is adequate for a signal.

Is that number 7 cylinder even firing? is it possible that the #7 coil is broken/cracked and arcing externally, sending a false signal due to leakage, into the wiring harness and feeding back into your crank signal. I would just unplug power from that coil and see if it will stay running, even though it will be missing.
 

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Discussion Starter #25
Is that number 7 cylinder even firing? is it possible that the #7 coil is broken/cracked and arcing externally, sending a false signal due to leakage, into the wiring harness and feeding back into your crank signal. I would just unplug power from that coil and see if it will stay running, even though it will be missing.
It was not that particular day. I did check spark more recently by pulling the plugs out of each cylinder and with them connected placed them close to the cylinder head and had my wife crank the engine. Each cylinder passed.

Just tried your theory and no dice but interesting though. Car doesn't run now. I've had the PCM in and out a number of time. I've never had the ignition on when it was out but it's possible I had battery connected with it out. My manual only referenced ignition on as the "no no" with the PCM unplugged but maybe my fuel trims reset and it's so far out of what I need.When I reset the trims with my Tech 2 it definitely took a long time to find idle again.

Anyway, I got tired of waiting for this company local to me to re-open; I doubt they will. Just ordered a new PCM from Rockauto and will send it and my old one to Brendan of lt1swap.com rather that tow the car to a dealer (one already declined the job). He should be able to copy my existing PCM coding to the new one.

Will update as there is more to add.
 

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Discussion Starter #28
First thing that comes to my mind is an isssue with fuel tank venting, but you'd probably know that if it was.
That's all I got.

:gto_rage:
Not sure, what would my indicators be? Apart from one brief episode I've never had an issue filling it with gas. I did fuck around with my fuel tank a fair amount as part of my build but more to do with the 8.1l bucket mod than anything else, and I'm assuming my steady fuel pressure measured at the rails rules out any fueling issues.

I have an idea. Need to go look at a wiring diagram to check it out.

have you checked the grounds for the ECM? Or in general?
I did. Just went out to double check everything again. The following are as measured with the harness backpinned and plugged into the PCM, ignition on.

Pin 1 which is just called "earth" in my manual- 0.1 Ohm to ground. 12.8V vs the + terminal (which was battery voltage), 0.0V vs the negative terminal
Pin 40 called PCM earth had the same readings as above.
Pin 21 is the PCM side of the ckp sensor ground reference and measured the same as above except there was a slight amount of voltage creep- .03 V vs the negative terminal
Pin 2 is the ckp sensor positive reference wire @ the PCM and it showed the same 11.5V as at the sensor end of the harness.
Pin 12 is the ckp sensor signal wire @ the PCM. It showed 0V when the sensor was off a tooth of the reluctor wheel and 10.6V when the sensor was on a tooth, as I turned the motor over by hand. Just turning the engine slowing with a socket wrench on the crank bolt each time the sensor went on or off a tooth and the voltage on the signal wire changed the fuel pump got a signal to run and you could hear it prime for 3 seconds.
 

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Discussion Starter #29
Also meant to mention on a previous day I confirmed each of the 3 sensor wires have less than .5 Ohm from the sensor end of the wire to the PCM harness.
 
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