engine starts but will not run.
what about spark and compression? sounds like the idle valve is stuck.try tapping on it while cranking.you said it starts but doesnt run.does that mean it cranks but doesnt start? or runs for a second or 2 then dies?the main relay maybe bad too if its not idling then dying.
My 87 bmw starts and runs for 30 secs then shuts off. Replace bad fuel pump and a bad fuel pump relay.
Check the three main relays in the engine compartment. One controls the ignition system. Also you ignition coil may be bad. But definitely have your fuel pressure checked out listen for a loud hum from the fuel pump. Could be your fuel filter is real dirty and has caused the pump to fail.
i PUT A NEW PUMP AND RELAY ON THE CAR JUST THE OTHER DAY AND WHAT IT DOES IS STARTS UP AND RUNS FOR A FEW SECONDS THEN SHUTS OFF. tURN SWITCH ON AND PUMP HUMS.
Also check you ICV (Idle Control Valve) also TPS (Throttle Position Sensor) on throttle body. And sometime the metal clip fails on the wire harness plug to the AFM (Air Flow Meter). Check that as well.
Check the lambda sensor.
^ It would still run with a bad o2 sensor
idle controlers on these engines can be coolant controled, this means a build up in them can jam them. can you make it run by holding a high idle when it starts or does it die regardless
it is a 2.8 Z3 it trys to start but i think it has no fuel it turns over as ok and does sound the same as when it normally starts but fires on some bores but then straight away cut out completely (2) months ago i changed the coils and fitted new plugs it has been running really well
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