2611 valve cleaner April 25, 2023 Solutions Central › Category: Maintenance › 2611 valve cleaner 0 Vote Up Vote Down robert hogg asked 2 years ago should engine be at operating temp before using 2611 intake valve cleaner? 1 Answers 0 Vote Up Vote Down chemtooler Staff answered 2 years ago Yes, for best results the engine should be at operating temperature. Please login or Register to submit your answer Username or Email Address Password Remember Me