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2007 Dodge Charger.
6.1L engine.
Built engine if that matters (bored to a 405, cammed).
OE crank tone wheel, OE cam gear.
After engine install we are getting a P0339 and a long crank. Not every time...not even most of the time. Always happens on initial cold start of the day and then might be fine the rest of the day... or not. Makes diag a lot of fun when the issue is inconsistent.
Clear codes and it might be fine for a while, might set the code the next time you hit the key.
Scan data shows cam/crank offset at .49 when both sensors are working.
Scoped the cam and crank and just this morning noticed (thank you Mr ScannerDanner for teaching me about Chrysler cam/crank sensors) that the crank sensor will be at 0V KOEO and may or may not rise to 5V at some random point.
If it does, the car seems to start normally. If it doesnt, it may be 3-5 seconds of cranking before I start to get a crank sensor pattern.
We replaced the PCM (due to a P0605 and inability to program the throttle) and the crank sensor shortly after replacing the engine (initial crank sensor would show 0 rpm when cranking), car left... and now its back. Sensor is an OE, PCM is reman (OE not available).
Not looking for any silver bullets here, just wondering if anyone had any suggestions for tests that I may have overlooked. I am in deep on this car at this point and I will admit to having gotten lost in the forest a time or two so far.
Plan to follow the suggestions tomorrow and unplug the crank sensor while its at 0V and see if it jumps to 5V as it should. (Also going to install a new, OE, crank sensor since I am that deep and the starter is already out.
I can attempt to post an image of the scope capture... if I can figure out how to do it. (Zeus scanner/scope - still REALLY green with it)
After learning more about how to actually USE my scope, I was able to scope the crank signal when it was acting a fool.
Initially I was getting a very intermittent crank pattern. The car would have no crank signal for the first 3-4 seconds of cranking, then would get one for a while, then lose it again...
So I pulled the sensor and replaced it with a new OE sensor. Checked pin fit while I was there as well as checked wiring from PCM to sensor.
All good.
Go to crank it... and no joy.
Still a no start. The data PID on the scan tool showed 0 RPM with an occasional spike. When I would get the spike the car would fire but not run.
Hooked the scope back up and scoped the signal wire at the PCM to see what was going on... and I had a picture perfect crank sensor pattern TO the PCM, but the PCM was not "seeing" it.
Nice crisp jumps from 0V to 5V and back... but no RPM signal.
So, at least in my heat damaged brain, this looks like a defective PCM.
