Could be your fuel pump, but most cases car does not start and just tries to turn over. Anyways, check you icv. Maybe not enough air/fuel mixture?
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Body: 318i 4 door
Mods: M50 engine, Jim C chip, light-weight flywheel, dual cat-back custom exhaust, 3:15 lsd, euro headlights w/angel eyes, 5300K HID, smoked corner lights, FK Motorsports foglights (crystal clear), ABS plastic upper eyebrow, clear side markers, M3 powered side mirrors w/LED, blacked out grill, M3 lighted shift knob, 17" ROH Furry wheels w/Kumho tires, Brembo cross drilled rotors and Hawk performance brake pads all around, PSS9 Bilstein and H&R coil over kit, front strut bar and Alpine alarm.