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Engine sputters, gauges go crazy

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Old Nov 19, 2019 | 08:37 PM
  #21  
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The voltage was holding at 4.7v steady. After the problem was solved, it is fluctuating, so i think one of the modules was leaking 5v onto the canbus.

But looking at the manual, star connector 2 houses the driver and passenger doors and the seat control, so shouldn't unplugging it have fixed the problem if it was the door?

I'll unplug the 6 pin door connector for now and start snipping star connector 2 wires if it does it again.
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Old Nov 19, 2019 | 08:52 PM
  #22  
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You’re likely to see a 5 volt reference on sensors and not on modules so I don’t think it’s that. Yes, removing the bus bar should have isolated those modules and made the car run normally...no need to cut those wires !!....you can de pin those wires !!...you were reading that voltage on the purple data line wire ??
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Old Nov 20, 2019 | 12:56 PM
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I was reading the voltage with the busbar in. All wires would be at the same voltage.

Last night I unplugged star connector 2 AND both RH door connectors and it still has issues.

I'll see if I can get it to do it again on the driveway and investigate the other modules.
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Old Nov 20, 2019 | 08:28 PM
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Got the car to do it on the driveway.
Measured CAN voltage, 6ish VDC this time. Started cutting wires and the bus voltage started fluctuating when I cut the PCM.
Read the DTCs, all the uncut modules are reading. Reconnect the pcm, all show no comm..
PCM CAN wire shows 9ish VDC. (The star connectir 2 and door are still unplugged at this point)

Then I reached under the hood and tugged on the PCM cables and everything came back. So it's either the PCM or the engine harness.
I'll swap out the ecu and see if I can do the "handshake"
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Old Nov 20, 2019 | 10:50 PM
  #25  
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update: I swapped the pcm and did the handshake.
Forgot that my engine is tuned and has big injectors...so it's running but undriveably bad.

I'll see if I can get it to have issues without driving.

On a side note, is there a way to copy my tune from the old pcm?
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