Hi i recently got a 99/00 jdm sti impreza engine and ecu put into my 96 wrx.

The guy who did the job couldn't find the bottom part of the air box . The car is idling funny and stalls sometimes at traffic lights. It really seems like a dodgy air flow meter but when i removed it the car idled differently - not better - just differently so it must be working. The guy says it is coz of the bottom of the air box being off?? He says the air flow meter is new. Could the air box cause this problem??

 

yeh that will cause this problem as its getting a different air flow rate. get one from a scrappy or post a wanted up