Over the past two weeks on every cold start, it has almost failed to start, at the initial turn of the key you get the first signs of life then it runs at what must be less than 300 rpm, you have to put your foot to the floor to get it to eventually fire into life properly after a good five seconds, tried cleaning the maf and resetting the ecu and no improvement

96 legacy twin turbo, orange maf which was recently installed, induction filter and hard induction pipe fitted along with zerosports ecu, been running fine for the last few months, boosts fine and idle is ok, does have a slight misfire though

 

Coolant sensor?.

 

I dont recall hearing the fuel pump whine on turning the key, could be a fueling issue, would it be a faulty pump or something with a regulator/fuse etc, standard pump on 150k