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CEL P11B0 Cam Shaft Actuator “B” Cylinder 4

While driving this morning I got a check engine light. Pulled out the Cobb Accesport and checked for codes. The code for the CEL was P11B0 Cam Shaft Actuator “B” Cylinder 4. After doing some research online I found there are 8 of these position sensors on the backside of the engine cover, two per cylinder. The numbering from 1 to 4 goes from passenger side to driver side on RHD vehicles. So since this error was for cylinder 4 actuator B then it’s the last one. This is what I found:

The cam actuator was slightly backed out, oil around it and the bolt holding it down missing. Well, that has to be the issue, now to find a replacement bolt. I pulled the bolt from cam actuator A Cylinder 1 to see if I could find a replacement.

It was mangled and not in good condition. Clearly when I had my valve cover seal redone the shop didn’t do a careful job. The top of the bolt was a T25 torques though it can be hard to tell from the picture.

After some more searching, I came up with part number N10622502 which I ordered 4 from the local dealer since I’m sure more are mangled too. They were cheap at 15 cents apiece.

Upon installation of the new bolt, I found out why it was missing. The hole was stripped and clearly backed itself out. Going to attempt some lock tight and see how it goes from there.