Hey folks, I've a g plate saff cossie running stage 1 with l6 ecu,t3 & hi lift cams. Over this past month I've been gathering up the bits to make her stage 3. Went out today with my 803s ( 2nd hand off eBay) and a brand new msd stage 3 chip. Got the injectors in & put the chip in & turned the key but she wouldn't start. Strong smell of petrol but no go. Put the stage 1 chip back in & started first turn. Defo had the chip in the correct way. Got another l6 ecu out off an e reg cossie I have, plugged the stage 3 chip in and she fired up at once. Now the problem I have is when the car comes on boost it misses badly and doesn't want to rev but is fine off boost. I set the plug gaps etc and ended up fitting the standard injectors with stage 3 chip & car goes perfect. Sorry for the story but what I want to know is 1, why does the stage 3 chip not work in my cars original ecu & 2, does it sound like my injectors are faulty? I tried tapping them but made no differnce. Thanks. Simon.