I have a 87 325e and it would crank for 30 secondes or more and then start when it was cold.
I am not sure what the part is called but I changed this
The little red square looking thing that is by the blue one. I am not sure what its called. But if you do change it coolant is goin to gush out of there if u dont relieve the pressure. I hope this helps you out.
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