Hi

I’ve got a recurring fault with my Focus and hoping someone can point me in the right direction. Vehicle is a 58 plate Focus 1.8 Tdci Style Estate with 95k on the clock. It starts and pulls away fine but as soon as I accelerate a bit harder the Engine Malfunction warning flashes up and the little red ‘i’ is lit on the dash. It’s not going into limp mode (or at least I can rev past 3,000rpm) but power does seem to be a bit down. Occasionally the orange engine warning light lights up as well and this will stay illuminated each time the engine is started until I clear it manually.

I’ve plugged in a generic OBD reader which shows no codes, but Forscan reports

PCM Module
P010F-F1 Mass or volume air flow sensor A/B Correlation
P0299-F1 Turbocharger/supercharger underboost

OBDII Module
P010F-C Mass or volume air flow sensor A/B Correlation


From that the MAF sensor would appear to be the first place to check\replace - I'll obviously give it a look over but is there any sort of testing or voltages I could check for to see if it's working properly.

Also I know DTC codes can often give a misleading indication of the fault so is this the most likely culprit or should I be looking elsewhere?

Thanks