Astra smoke on acceleration

Hey! Yeah, those sensors can be a pain. Smoke on acceleration definitely points to an emissions issue. Is the car running rough at all? Like, misfiring or idling funny? What kind of smoke is it? Black, blue, or white-ish?

The car seems to idle okay, no obvious misfires. The smoke is black. Could a faulty sensor really cause that much of a rich running condition?

Black smoke is unburnt fuel, so yeah, way too rich. The sensor probably feeds bad data to the ECU, messing with the fuel/air mix. If you're sure it's the sensor, replacing it might fix it. Otherwise, you should get it checked by a professional.

Thanks for the insight. Indeed, it was the exhaust back pressure sensor. Replaced it, and the problem is gone. Cost me 245€ including the part and labor. Appreciate the help!