Have to back off cam sensor cap to start

I put a Casper Cam Sensor cap on my TTA recently to try to fix my code 42 issues. After setting the 25 BTDC according to the instructions, my car barely wants to start sometimes. It turns over slow and backfires. If I turn the cap CCW several degrees it seems to start OK. What is going on here? I really don't understand what exactly the cam sensor is for.

First, take the cap off the sensor,then the phillips head screw and pull the little wheel off and see if the locating tab is gone. These brake and the wheel keeps moving. RJC makes a repair washer for this very thing.

I have read and it works... with crank at 25atdc point dot in cam gear at pass fender and drop in cam sensor sensor. Align the stake tab on rotor with the tab on the sensor body that is used to orient the cap.

I went thru something similar with one. If i loosened one of the cap screws a couple of threads it ran fine but as soon as i tightened it down it ran like crap.

Nothing against Casper's. maybe mine was just bad.

i went back to the stock cap with no issues.
same thing

Sent mine back to Caspers the new one worked perfect.I notice when you rotate the cam sensor the light did not always light up unless it was lose