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m20 fires/starts but wont stay running, has fuel/pressure, has spark.

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    m20 fires/starts but wont stay running, has fuel/pressure, has spark.

    I recently bought a 1986 325 that had a broken timing belt. I had an extra m20b27 that I refreshed with all new gaskets and what not before swapping. To the point where the motor is installed and finished but the car will fire and seem like its starting but once it starts it will immediately die even while continue to crank. I check the fuel pressure with a tester and it checked out fine. That should mean fuel pumps and all are fine right? checked spark with spark plug wire and screwdriver on bare metal and it sparks and pulses. I checked for intake leaks, found a huge hole in the intake boot but replaced with aftermarket one I had lying around while another one ships. But didn't really change anything. I tested TPS with multimeter and was fine and also tried swapping out AFM's and idle valves of the motor with broken timing belt but ran fine before. I tested the cold start valve and was fine.e I checked that everything is hooked up correctly, I have been reading the Bentley and have tried quite a lot but nothing I do really changes how the motor tries to start. I looked at the motors casting marks and saw that it was made in 11/84. I read somewhere that the ecu's changed in 85 and the engine harness I used was with the 84 motor. The ECU number is 0 261 200 02. will this combo work? running out of ideas.

    #2
    I'd suggest putting an inline spark tester on your coil wire and see if something is causing your spark to die. I'd also take a good look at your cap and rotor just because. If your fuel pressure regulator dumps your fuel pressure on you, it will quit running. Also put a test light in line to your fuel pump circuit to see if you lose power there once the motor starts. You can jumper your fuel pump relay to verify the pumps are working. And finally, do you have any gas in the tank regardless of what the gauge says? Ask me how I know...

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