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Re: <E30><M3>Hard Starting Problem...the continuing saga



> I'm still having a hard start problem with this car...some specifics...

>1990 M3 (S14 engine); 49K miles

>Symptoms:  Starting capability has deteriorated over the last 10K miles.  No
>difference in cold or hot starts.  It can catch on the first crank, but usually
>takes 5-6 (as many as 10) attempts to get it to catch and fire up.  Runs
>perfectly after started.  10K miles ago it started on first, possibly 2nd crank
>each and every time.

>Recent replacements:  fuel filter; distributor cap; rotor; correct Bosch
>sparkplugs; MBE main relay (said to be intermittent)

Your fuel pressure may be bleeding away and the pumps need
to run a while to build up pressure in the fuel rail again.

Buy a fuel line clamp and with the engine off put it on the
incoming fuel line. Leave the car an hour, remove the clamp
and try to start it. If it goes first time you may have
found the problem, if not try the outgoing line.

One end of the fuel rail is held high by the fuel pressure
regulator, the other by the non-return valve on the fuel
pump. If these are OK and the problem persists then it may
be a bad injector (which may show up as black smoke when you
start). A fuel pressure gauge is better but costs more!

- --
Who needs a life when you've got Unix? :-)   
Email: john@domain.elided, John G.Burns B.Eng, Aberdeen, Bonny Scotland
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