Porsche Enthusiasts Club Forum

HI guys just done fuel pressure check with oil filled gauge got 3.1 BAR with VAC connected and 3.4 BAR with VAC disconnected car is a 1987 S4 . Its got a Bosch motor sport fuel pump fitted (FLOW RATE 100 LITRES PER HOUR AT 5 BAR) Also a new Porsche fuel pressure regulator has been fitted have I got to much pressure cheers.

Hi

That pressure is equal to 45 to 49 psi...

On mine as part of my Nitrous system I have a fuel pressure transducer fitted to the end of the drivers side fuel rail permanently going to my Electronic Race controller, so I can see my fuel pressure all the time.......(its probably where you got the readings from)

My pressures are as follows ...IDLE = 42/43 .... MIDRANGE under acceleration = 48/49 and full blast WITH NITROUS = 52/54

So your pressures are all fine....

All the best Brett

That's spec for an S4 where pressu would be 3.3 Bar +/- 0.2 with engine idling.

If you just run fuel pump with engine off for a few seconds (by bridging relay) should read max 3.8 bar

Thanks for replys