[ItsDefinitelyYourPCMBro]

Hey guys, more follow up here. Did a key dance to get MILs and this was my result:

12 22 23 34 42 51 54 55

12 is battery disconnected within last 50 key cycles
22 is engine coolant temp input above or below expected levels (ECT shares the same ground as camshaft and on my engine, literately splits off in the harness right at these two sensors, I see normal operation so I don”‘t suspect this as an issue, most likely bleedover from can circuit errors).
23 IAT above/below expected levels (once again, this sensor is the next in the circuit from the camshaft and is on the same wiring harness that runs underneath the fuel rail – I’m suspecting ny issue lies in this harness.
34 open or shorted condition in the speed control circuit (the PO1596) probably will just pull the cruise control fuse because I don’t use it and this DTC is very annoying and counterproductive to diagnosis
42 open or shorted condition in the auto shutdown relay (from the cam sensor shorting)
51 Lean fuel/air ratio detected by excessive rich correction (this one probably set when I had a minor hydrolocking incident recently (obviously when water is introduced to the intake the engine displays a lean condition and rich response before halts to a stop. Lucky for me, it almost immediately restarted with no sign of internal damage. Just ran shoddy till she got the water out of the exhaust)
54 no cam signal detected during crank
55 End of MIL sequence

Speaking of the hydrolocking incident, ironically since that happened I cannot get that ground wire to display any resistance whatsoever now and so the engine has started every time. I have a new CEL though now, and haven’t been able to pull the DTC yet, but it went off and stayed off, but displayed on restart so it had to have been set today so maybe when I can actually pull that with a scantool we’ll get an idea of what is happening now.

[ItsDefinitelyYourPCMBro]

Just wanted to give a quick update – the troubles continue into today, but I have been able to gather some more data.

Here are the DTCs for my 1996 Dodge Intrepid 3.3L V6 176,xxx

PO340 – Camshaft Position Sensor Circuit Malfunction
PO1596 – Speed Control Switch Always High

The car will start when the resistance on the ground wire to the camshaft sensor is at the proper 0.05ohm reading. So I can tell my car will start as soon as I can get this reading. However, what was once an occasional intermittent issue has developed into every time the car is turned off, it will not restart.

I can’t seem to find any pattern to this behavior. Having an assistant hold my DVOM in place, no amount of adjustment to the wire or the connector itself will drop the resistance. So in an attempt to create a manageable and observable change in this behavior, I started at the very beginning of the entire circuit. With DVOM in place, I adjusted the positioning of the
hot batteryy terminals and observed an immediate DVOM response – reading changed from 0.39 to 0.31. Intrigued by this, I removed the hot terminal entirely and the DVOM stabilized at the wire at 0.05ohms and stayed there. I’m not entirely sure what to make of this new information yet, but from what I’ve gathered, the speed switch code could either be an additional result of a bad chasis or engine ground or the cause of the problem if that circuit is running too high and bleeding over into the PCM circuit. It’s amazing to me I can get this car to start and stay running at all, considering that according to my wiring diagram, the entire PCM circuit uses the same blk/lt blu ground wire.

To me, it seems most likely that there are crossed wires or circuit bleedover somewhere – specifically, a hot wire and that black ground PCM wire touching intermittently or something. Anyone have any ideas? I really need help with this diagnosis.

(Also, I was able to note somewhat of a correlation from temperature and resistance. Seems as temp goes down, so does resistance. A friend noted light corrosion on the hot battery wire. I’m trying to figure out how to isolate the part of the circuit causing this resistance but I was able to verify by pulling a few other sensors that the resistance is shared through the circuit.

[ItsDefinitelyYourPCMBro]

A healthy engine would stay within 0-5 negative or positive at all times. There would be observable, but normal correction of the fuel trims but ideally I look at a healthy engine as within 0-5 either way and no higher than 10.

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