manifold absolute pressure sensor implausible signal cars running rough as a dog sounds like its on 3 cylinders any help would be great   

It's most likely the boost pressure sensor or the wiring. Recently, I've seen this error on a few cars where the ground in the plenum chamber is badly corroded.

It's most likely the boost pressure sensor or the wiring. Recently, I've seen this error on a few cars where the ground in the plenum chamber is badly corroded.

changed boost sensor and soldered new plug on wheres the earth u talk of? steve

Edited 4 March, 201412 yr by steveopc

BUMP

Take a look at the LH suspension strut. There is either an earth on the strut or if it's not there, it's in the plenum chamber immediately behind.

What year/engine is it?

Take a look at the LH suspension strut. There is either an earth on the strut or if it's not there, it's in the plenum chamber immediately behind.

What year/engine is it?

2005 fabia vrs 1.9 pd130 engine

could also be a mechanical engine fault ie inlet valve stuck open so the map sensor is not getting the reading it is expecting, it should run ok on idle even with the map disconnected if the engine sounds like it is missing then I would start with finding out why, either injector or compression problem.

check the egr is not stuck fully open too if you still the valve fitted

stripped loom dwn today cleaned earth and all lights out but still the same no fault codes though am I right to be thinking the cams naffed?