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Re: Warm starting problem (look for fuel pump check valve failure)

 Hard starting after engine is warm and sitting for a short while:

 >- when hot it would start immediately after being shut off

>but....

>- if it had soaked for 1/2 hour or more when hot it would require 4 to 8 seconds of cranking... but
would always start, eventually

>Diagnosis:
> The check valve in the main fuel pump was leaking allowing the fuel injector rail residual
pressure to bleed off resulting in formation of a huge >fuel vapour bubble in the fuel rail and back
down the fuel line toward the pump. The extra cranking time was needed by the fuel pump to
>recompress and eliminate the fuel vapour bubble in the line and repressurize the fuel injector
rail.

 I have a very similar problem with my E12  79 528i (also in Houston).  Question: Does the electric
pump operate for a short period of time when the key is on the 'ON' position, or does it only
operate while the starter is cranking and then while the engine is running?

How did you find out the check valve in the fuel pump was leaking? or did you just suspect it was.
I don't know if my fuel line is the same size as yours (3/8"), anybody know? 
I'd like to try this solution.  Could you send me the phone number and parts info from Daytona
Electric.

           Thanks, 
           Sergio ...
           [email protected]
        
          79 E12 528i ...