Going to post this here in the hopes it will help someone else with this unusual problem.
These codes relate to the bank one exhaust cam sensor.
After a quick swap between the intake and exhaust sensors to rule out a sensor problem and see if the code followed, I then started looking into the wiring to the PCM and found no problems. I then pulled out the scope and check for a pattern at the ECM and found a good waveform. Not quite convinced it was an ECM issue as these trucks are known for timing chain issues. I followed all the diagnostic routines in shop key and even found a TSB that all pointed back to timing issues. Tore the truck down and found timing chain was worn and tensioner was completely extended. Replaced chain and all related components only to find the codes still returned. Again retested all circuits and confirmed I had a good waveform at PCM. However this time, and what I should've done the first time, was compare the exhaust cams, right and left bank to each other, that's when I found my problem. The bank one exhaust cam drives the vacuum pump mounted to the back of the head. The drive coupler for the vacuum pump is pressed on the back of the cam and is also the tone wheel for the cam sensor. This one had slipped nearly 90* from its original postion.
Some noted data pid information to help diagnose if you don't have a scope.
All VVT data was frozen, all zeros.
Fault PID data showed fault with bank 1 cam sensor 2 and also oddly enough bank 2 intake actuator.
Function tests of VVT actutors would not work.
I have to pictures and will try to upload them soon.
Fix was replacing the bank one exhaust cam. Also replaced vacuum pump as it may have been root cause.
These codes relate to the bank one exhaust cam sensor.
After a quick swap between the intake and exhaust sensors to rule out a sensor problem and see if the code followed, I then started looking into the wiring to the PCM and found no problems. I then pulled out the scope and check for a pattern at the ECM and found a good waveform. Not quite convinced it was an ECM issue as these trucks are known for timing chain issues. I followed all the diagnostic routines in shop key and even found a TSB that all pointed back to timing issues. Tore the truck down and found timing chain was worn and tensioner was completely extended. Replaced chain and all related components only to find the codes still returned. Again retested all circuits and confirmed I had a good waveform at PCM. However this time, and what I should've done the first time, was compare the exhaust cams, right and left bank to each other, that's when I found my problem. The bank one exhaust cam drives the vacuum pump mounted to the back of the head. The drive coupler for the vacuum pump is pressed on the back of the cam and is also the tone wheel for the cam sensor. This one had slipped nearly 90* from its original postion.
Some noted data pid information to help diagnose if you don't have a scope.
All VVT data was frozen, all zeros.
Fault PID data showed fault with bank 1 cam sensor 2 and also oddly enough bank 2 intake actuator.
Function tests of VVT actutors would not work.
I have to pictures and will try to upload them soon.
Fix was replacing the bank one exhaust cam. Also replaced vacuum pump as it may have been root cause.
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