fuel pressure regulator correct operation?

zen said:

i assume that a correct fpr should hold the pressure to the fuel lines even when motor switched off..ie so that if you just took off fuel pipe from fuel pump you would get a good covering in fuel..hense there is a safe way to depressureisse sytem when working on it...???

so...the fact that my aftermarket fpr drops the fuel pressure soon as fuel pump turned off indicates its a piece of poo???

thoughts please before i go andf buy another...(need one that has rising rate when seeing boost)

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JD. said:

Hi Zen,

Fuel pressure should remain even with engine off, fuel system on the P38 is depressurised by disconnecting the fuel filter (according to RAVE and that's how I do it) though you still get a good spray of petrol.

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zen said:

"Fuel pressure should be constant. It's the delivery from the injectors controlled by the ECU that controls fuel quantity not the fuel pressure regulator."

not so..it relys on fpr keeping pressure x psi above manifold pressure.ie it varies thats why it has a connection to manifold..(stock non supercharged fpr)anyway boosted,running 8psi...now i need more fuel psi when on boost..



(sorry its late,dont intend to sound harsh)

back to question...so i guess my aftermarket fpr is crap..cos it dont hold the pressure once fuel pump switched off..

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zen said:

toyota quad cam v8 supercharged in 1972 rangie..

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