I have a 2001 impreza wrx and just had a replacement engine fitted. My problem is it will only run if the MAF sensor is unplugged ?????? A new MAF has been tried but is still the same. Any ideas or help on what the fault could be would be much appreciated.

 

Sounds like it could be a boost/vacume leak ...check all the hoses etc especially if you have a front mount fitted , and also check that the maf hasnt been put round the wrong way as i have seen this done

also well worth getting it plugged in to a fault code reader , hopefully there will be a fault code with an answer for you .

 

Thanks for the advice im going to go through it all tomorrow. As i said we have tried a new maf but the problem was the same and as it has an induction kit the maf only fitted 1 way but thinking about it i bet the induction pipe is the wrong way round thus making the maf back to front so 1st thing tomorrow i will turn it round and try it.

 

Has it had a remap and set to run mafless?