i’m maxing out at 55psi WOT, my old twin pump XJR goes above 70. anybody have another car to compare with?

i know the panpag cars have slightly better injectors

thanks

 

Did you ask in the X308 or X350 forums?

 

Whether 1 or 2 pumps your FP should be higher than 55 psi. My FP is 55psi at idle, varies between 53 and 58 psi when driving and when I floor it FP increases to 65 - 70psi. I have 2 FP's though in my 04

 

yea that’s what i figured, my 04 xjr hits 72

06 str only 55. with 240k mi it’s probably time for a new pump.

 

It might pay also to check the vacuum boost reference line on the back of the engine.
to the fuel pressure regulator is connected snug with no cracks or leaks.
Also , it pays to compare OBD2 Fuel pressure to a mechanical fuel pressure gauge on the fuel rail.
before throwing pumps and parts at it.

 

schrader would be nice but it was deleted in 06. have to trust the FRP sensor