i just bought a b and m fuel pressure guage whihc i attatched to the service port on top of the fuel filter..

at idle its 40 psi with the top hose of the fuel pressure regulator off it jumps to 50 psi.. is it suppose to be at 40 psi? is this why im getting bad gas mileage?

what do i need to check next/fix?

i also just bought a fpr that i need to install will that fix the problem? or should i fix the problem before i intsall the fpr thanks

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dchung1 &raquo;</TD></TR><TR><TD CLASS="quote">... i also just bought a fpr that i need to install will that fix the problem? or should i fix the problem before i intsall the fpr thanks
</TD></TR></TABLE>As long as there's no obstruction in the fuel return line, the FPR is what controls fuel pressure. So put in the new FPR & see what happens.

 

ok thanks

 

also does anyone know the diameter of the fuel return line hose i dotn know if my hose is too small may impeding the flow the hose is pretty skinny.


my current fuel return line hose is about 3/16 inch think connecting to a T connection going to the throttle body and the sensor. is 3/16 diamter hose to small

also does the fuel pressure reading need to be with the car warmed up or just running with top of FPR hose off?

Modified by dchung1 at 9:37 AM 10/29/2004


Modified by dchung1 at 9:42 AM 10/29/2004

 

With the hose off it's supposed to be higher by ~10 psi. That's the pressure you use when adjusting it also.

 

You take off the vacuum hose for adjusting, you don't take off the fuel return hose...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JimBlake &raquo;</TD></TR><TR><TD CLASS="quote">You take off the vacuum hose for adjusting, you don't take off the fuel return hose...</TD></TR></TABLE>

Who said you take the return hose off...

 

thats wierd in the instructions for vtec manual it says when taking the pressure measurement you take off the top of the fuel pressure reg hose (NOT the fuel return line which is the bottom!) then take the measurement which should be 38-42

just want to confirm this... becuase i researched on ht threads and some people say that the guage should read 40 but dont mention anything about disconnecting the top of the fpr hose and then thats the reading you should be looking at


can anyone confirm this?


Modified by dchung1 at 4:49 PM 10/29/2004

 

justinstalled the bm fpr and adjusted it to 42 psi with vac hose off so hopefully i get better gas mileage now

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dchung1 &raquo;</TD></TR><TR><TD CLASS="quote">my current fuel return line hose is about 3/16 inch think connecting to a T connection going to the throttle body and the sensor. is 3/16 diamter hose to small</TD></TR></TABLE>The small one is the vacuum hose, but it sounds like you figured that out in the later post. I hope the fuel return hose isn't connected to the TB & sensor...

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GeeReg &raquo;</TD></TR><TR><TD CLASS="quote">Who said you take the return hose off...</TD></TR></TABLE>I was just hoping that dchung1 wasn't gonna get them confused...

The fuel return hose is the bigger one at the bottom, it returns fuel to the tank. The vacuum hose is the one going to the throttle body or intake manifold.

You disconnect the vacuum hose & plug the hose so it's not a vacuum leak to the manifold. Leave the vacuum nipple on the FPR open.

 

yep i meant that i left the fuel return line on the fpr. just disconnected the top vac hose of the fpr for the reading.