Ok history of the car is unknown I have service records up the 200 k mark from dealer nothing after that . ? Is I am going back into it and look at the valve cup for complete stroke or movement of the valve I am going to try and find a scope to inspect the inside can the seat be seen with a brite light and is there a way to post video on this site. I have only replace/ rebuilt injectors and all fuel lines and filters and heat shields head removal is not out of the ? But would rather not What a source for parts for the 606 seems like they are very scarce in middle ga. Anyway. Thanks