So, possibly like a fool, I removed the CPS housing to change my thermostat and am now getting the P0017 code. I tried not to move the hex key when I had the housing off but am assuming I did. From what I have read, I have to line up the timing marks on the hex key and on the housing and reinstall with the #1 cylinder at compression TDC. Is there an easy way to verify TDC on the compression stroke or have I got to remove the valvecover to do so?

 

Removing the valve cover is the easiest way and should only take about 2-5 minutes (~10 bolts).

Intake cam gear should have the INT mark at the 2 o'clock position; Exhaust cam will have the EXH mark at the 10 o'clock position.

Pull the hex out, take the sensor out of the housing. Line the notch in the hex up with the "tab" that's on the side of the housing.

Stick your finger in the sensor hole to hold the hex steady. Insert into cam. Torque bolts. Reassemble.

I'll stress that it's important to follow the toque specs on the valve cover bolts - they break VERY easily. 89 in-lbs, IIRC.

Reference images below.

 

Thank you, Hopefully I can get this tackled this weekend.

 

I guess that I should add that there's a TDC mark on the timing cover that will align with a notch on the back side of the crank pulley. It's very difficult to see while the engine is in the car. I don't know why the clowns made the marks align on the top side of the pulley, instead of on the bottom side.