I’ve got a 2000 VW Lupo 1.4 automatic. (It’s a smaller hatchback version of the Golf). Acceleration is a bit sluggish and the gas mileage is a bit lower than it should be, compared with other Lupos. Combined mileage is about 31miles/US gallon. I’ve been doing the usual things to improve gas milease; new ignition leads, plugs, cleaned the throttle body and the MAS sensor, to some good effect. The question now is should I clean the downstream O2 sensor? As the sensor is screwed into a rusted exhaust manifold, I’m concerned that trying to unscrew it, even with the aid of some de-rust spray, might turn a small problem into a big problem if the thing breaks off.
So far car’s computer has no warning about the O2 sensor. Has anyone had good experience with gas additives like Wynn’s that promise to clean the O2 sensor? Any advise, suggestions welcome.