In a message dated 4/1/2006 12:53:53 P.M. Central Daylight Time,
peter.rees01@tiscali.co.uk writes:
When I start again from warm, its a cow to start - sounds like an old bus -
then when it does get going, runs great at 2,3 and 4k but at 5000 RPM, I get
a sudden and quite substantial (300) drop in RPM - Eventually, this goes
away and again, it seems fine.
Peter,
The 914s have a mixture enrichment feature that kicks in at around 5000 rpm
to prevent detonation during boost. The TCU commands a 3-way solenoid to
switch from a low to high pressure source in the airbox effectively increasing
the pressure in the carb bowls via carb vents to slightly richen the mixture.
If the enrichment valve is not operating properly, you could be dumping too
much fuel in the mixture at the switching point. You may want to check this
valve.
Just a theory,
Tam
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