Testing Fuel Pressure

[roccorich 16]

Hi

 

How do I go about checking fuel pressure.

 

Ive got a guage but what connections do I need and where should I plumb it in?

 

cheers

 

Rich

Edited October 15, 2013 by roccorich

[daneldridge23 15]

have you got an inline regulator?

[roccorich 16]

Dont think so.

 

Just want to check Im getting enough pressure as the cars running very lean.

[DamirGTI 327]

Depressurize the system - start the engine and whilst running remove the fuel pump fuse from fuse box , let it running until it shuts down , then fit the fuse back .

Connect the gauge on the main fuel feed line (fuel filter to fuel rail) , either directly on the rail if you have appropriate fitting along with the gauge , if not by using an T piece fitting splice it into the main fuel feed line .

 

Undo the vacuum hose from the back of the reg. during the test , start up the engine , if it's fine it should maintain 3Bar pressure .

 

If you suspect that there's something wrong pressure related (low pressure) , use vice grips and with the engine running and gauge still connected pinch the fuel return hose (from the reg. back ..) - if the pressure goes up , the fuel pressure reg. is faulty .. opposite scenario - if the pressure lowers suspect fuel filter blockage , fuel line blockage , fuel pump (often cause - degraded/leaky rubber hose which connects fuel pump housing with the fuel pump)

 

D

Edited October 15, 2013 by DamirGTI

[roccorich 16]

Cheers Damir.

[roccorich 16]

Wouldve helped if Id remembered to disconnect the vacume hose like you said. doh!!!

[petert 554]

Another way of testing is to plumb the return hose into a measuring cylinder/bucket. It should flow 500mL in 15 sec. (2L/min).