1998 SLK230 with 61,000 miles: CEL with codes P0341 (CAM POS Sensor Range/Performance) & P0410 (Secondary Air Injection Sys Malfunction).

Car is slow to accelerate and tends to bog down on up-hills without down shifting appropriately. Have reset code and returns at varying intervals (intermittent).

Have not found the smoking gun yet. Troubleshooting so far includes: No loose connections, vacuum lines okay, clean MAF, and clean throttle body.

CAM Position Sensor shows 8 ohms resistance both cold and hot. With key ON, voltage is 12 volts & 7 volts at the plug connectors (each wire).

Should my next step be to change the CAM POS Sensor?

 

Replaced the Cam Pos Sensor ($140) and all codes vanished. After 2 weeks- no repeat.

 

what's the best mechanic that anyone can refer to me.
I have SLK 230 , 1998 and the Camshaft Pos Sensor needs to be replaced.
How difficult to replace it, can I do it myself? If not is there any recommendation reasonable mechanic . I live in Northern California(San Francisco Bay Area)

thanks

Francis