JoeHorner
Senior Member
- Joined
- Aug 21, 2022
- Messages
- 132
- Reaction score
- 165
- Your Mercedes
- 2003 W203 C270CDI Elegance
Long overdue update on this one.
About a year after getting the car it still goes into no boost / max 2000rpm if you come to a stop +junctions, roundabouts etc) after about 10 mins of driving.
Turning it off and on again reliably puts everything back to normal until the next stop.
There's no MIL light and the only code (from icarsoft) is 105-128 map sensor plausibility.
Watching the MAP sensor through OBD (icarsoft doesn't offer live data any other way for this model) the readings look plausible other than it seems to read about 2kpa lower than atmospheric when sitting engine off (atmospheric checked with a decent Barometer & confirmed by the Met office for Valley which is about 3 miles away). I accept that the sampling rate on OBD is too low to spot spikes etc but for now it's all I've got!
It will also set the code after a couple of minutes sitting with ignition on / engine not running which seems to rule out any turbo leaks etc.
I can't find anything in the manual, does anyone know if this engine has an ambient pressure sensor to compare the MAP with?
About a year after getting the car it still goes into no boost / max 2000rpm if you come to a stop +junctions, roundabouts etc) after about 10 mins of driving.
Turning it off and on again reliably puts everything back to normal until the next stop.
There's no MIL light and the only code (from icarsoft) is 105-128 map sensor plausibility.
Watching the MAP sensor through OBD (icarsoft doesn't offer live data any other way for this model) the readings look plausible other than it seems to read about 2kpa lower than atmospheric when sitting engine off (atmospheric checked with a decent Barometer & confirmed by the Met office for Valley which is about 3 miles away). I accept that the sampling rate on OBD is too low to spot spikes etc but for now it's all I've got!
It will also set the code after a couple of minutes sitting with ignition on / engine not running which seems to rule out any turbo leaks etc.
I can't find anything in the manual, does anyone know if this engine has an ambient pressure sensor to compare the MAP with?
