1985 635CSI-- Cranks But No Start When Hot!

[Red 635]

Hi I am a backyard mechanic.. so I'm told... (I've rebuilt M52TU engines on my own) I have a 1985 635CSI. In the garage cold, starts right up, runs a little rough but it runs and drives. Once it's hot, shut it off and let it sit for a few minutes, it will not restart until it cools off or sits for a few hours. It cranks, does this occasional brief moment where the starter bogs down, then keeps cranking. The bogging down is almost like a cylinder gets bound with fuel or something. Once you let it sit for a while and temp goes to pretty darn cool, it will start but run rough for a few minutes. I replaced the coil, no change. I tried the check for codes pedal 5 times thing... doesn't seem to work.... I'd rather not just throw parts at the car. If I crank it enough I can smell fuel. I think its a sensor problem. I'm guessing a position sensor. Only a guess. Any help would be appreciated. Again, I'd rather not just throw parts at it.

[wfwright2]

Not an expert but !!

Check the temperature sensors, the nasty cold start injector first. If it is running ok once started it is probably not the position and speed sensors on the bell housing.

Find the electricsl trouble shooting manual for your year, it will provide the specs and a procedure.

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