Quote:
Originally Posted by Redd
In preparation to do my valve covers I asked two of my trusted mechs (both M specialists) if it was necessary to do the spark plug tubes. Both of them said they have never replaced plug tubes on E9x platform. E46 plug tubes turn brittle and need to be replaced when doing the valve cover, but the plug tubes on E9x M3 don't have this problem. 
Fwiw, my car is 144k kms and on original spark plug tubes. I didn't change them the last time I did valve covers. No issues so far. |
I bought some to have done because $64 doesn't seem like a major deal in the scheme of things, however, I will ask my shop too and if they see no need for them being replaced I will just stick these in and consider it a life time replacement unless failure occurs.