Blue Devil Stop Smoke and Engine Repair (16 oz)

When blue or gray smoke starts coming out of the tailpipe, it usually means oil is getting past worn seals or rings and burning in the combustion chamber. Blue Devil Stop Smoke and Engine Repair is a 16 oz oil additive formulated to address that smoke and reduce oil consumption by conditioning worn components in the oil system.

What sets this apart from some competitors is that the formula contains no solids — no particles that could clog passages or create new problems in the engine. You add it directly to the crankcase oil, and it works through the system to help recondition seals and reduce the gaps where oil slips through. It is compatible with all engine types and safe for all oil system components.

This is the kind of product that works best on engines with moderate wear. If your valve seals or rings are severely worn, a chemical treatment may provide temporary improvement rather than a permanent fix. For engines that are just starting to show smoke at startup or under load, it can be a practical first step before committing to a more involved repair.