Joseph.

I've been driving MB Diesels for 35 years and have yet to clean or calibrate an injector.

I did replace 1 or 2 injectors when there wae a noticable knock in one cylinder. I took an injector out of a parts car/engine I had and replaced the injector that was causing the knock. Problem solved.

I have had an IP or 2 rebuilt and calibrated, though.

P E H