GC8 Tapping noise and Knock Sensor code
 

Having an issue with my GC8 MY00 Turbo, recently had cambelt and oil pump, crank sensor and the MAF cleaned, and run fine for 500 miles, mixed driving. On a slow 5 mile drive the Check engine light came up, drove home very slowly, opened the bonnet and there is a tapping noise from near cylinder 4 somewhere.

Looking at videos online sounds similar to people with injector issues, or loose spark plug. Engine does have an occasional very very slight rumble feeling when idling you can just about feel through the seat at idle, about every second and a half? I read the codes, 11 and 22, reset and turned over with nothing coming up. Any suggestions? Safe to drive about 50 miles to a Subaru place or best to find somewhere local? Advised possible big end or little end by different garages when knock sensor replaced beginning of December 2016 :(

Any guidance or anyone local to Nottingham able to help/listen would be greatly appreciated

Have you checked if the plug is loose?
Who fit the Cambelt? Might be worth checking to see if it's still tight and hasn't slipped.
Hard to diagnose a noise online but if you can get a sound clip or video then might help people give advise.

I haven't yet but going to do that tomorrow. Had it done by Simon at APi, I have a clip of the noise I'll find a way to post it

Afaik API have a good rep so you should be ok knowing the belt has been fitted correctly.
I would check the plug is in ok and have a look at the exhaust manifold&gaskets.