in article d0fe0c$sgi$ snipped-for-privacy@titan.btinternet.com, Tom@Saabtech at snipped-for-privacy@btconnect.com wrote on 06/03/2005 17:18:
It sounds like you may have a problem with the warm up regulator, [fixed to
> the side of the cylinder head by the thermostat housing], it should have a
> 12 volt supply all the time the engine is running. The 12 volt supply and
> heat transfer from the the cylinder head works on a bi-mettalic strip which
> controls the fuel pressure to the fuel disributor and thus the injectors,
> when the engine is cold the pressure is higher and as the engine warms the
> pressure lowers [control pressure], If said device is fault then it makes it
> immpossible to correctly set idle speed for both cold and warm. You really
> need a fuel pressure gauge to diagnose properly, but a good indication is if
> you have access to a co meter, disconnect the vacuum/pressure hose that is
> fitted to the regulator, plug the manifold and apply about 10 psi to the
> regulator and this should increase the co to about 7%. If no difference or
> a small increase is noted then the diagphram inside the regulator is > knackered.
Hi Tom ... Just to recap on this one. When the engine warms, how does the system lower fuel pressure? Does the bi-metallic strip open or close current to the fuel distributor?
Paul
1989 900 Turbo S
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