I posted this on the Cadillac forum and I haven't gotten much feedback so I'm posting it here.
I recently purchased a 2004 CTS with the 3.6L engine
. I bought it cheap due to the timing problem. The timing chain broke on the previous owner. He had the timing chain replaced. The car would start and run ok-ish but idled rough. The mechanic did the job again the car ran the same. After that the previous owner decided to unload it and I bought it.
The codes are P008, P0016, and P0017. I've done lots of research and reading on those codes and the combination of those codes with respect to the 3.6L engine
. I looked at the camshaft
position values with a Tech2 and I found something I don't understand. This is what is going on:
1) Clear the codes
2) Start the car
from cold, idles a little rough, no check engine light
3) Monitor the CMP (camshaft
position) values with the Tech2
At first "Int. CMP Angle Bank 1" is at 37 degrees and the desired is 0 degrees. The other three camshafts
show 0 degrees for both the actual and desired angle. All four CMP band commands are 6%. After a short period of time "Int. CMP Angle Bank 1" works its way down to 0 degrees. The command to that camshaft actuator is always 6%. I don't understand what is going on. The codes that eventually show up are for both the intake and exhaust camshaft position on bank 1 but I never see anything odd on the Tech2 for the exhaust side.
A video of the Tech2 screen is below:
I have tried swapping the camshaft position sensors around but the problem didn't change. I also pulled out the crankshaft position sensor and used a borescope camera to verify that the reluctor wheel was correctly positioned on the crankshaft. It looks like the next step is to pull the front of the motor apart but I'll wait a few days to see if anyone has other suggestions.