This relates back to a thread from a couple of weeks ago that has probably expired by now. Original problem was loss of power on a Merc C200 CDi - this was intermittent and (obviously) didn't display itself when the car went for its scheduled service. I finally got around to reading the codes when the engine management light came on - results are P0299 (Turbo underboost) and P2A00 (O2 sensor circuit range). I *think* that what is happening is that the car doesn't like the O2 sensor and accordingly is running the engine in emergency mode - this would account for the loss of power and rpm restriction. I *assume* that the turbo message is caused by the engine running in emergency mode - though this may be wrong. So, if the real cause is flagged up by the P2A00 message, ie an O2 sensor fault, how to find / fix it?
- posted
15 years ago