whats up guys i have an 02 x 2.5 sport with a intermitent hesitation problem that only occurs when entering Hway on ramp with long banking right turn when car levels out after turn its runs cherry um going nuts i cant pin down the problem ithink its fuel related but dont know what correct fuel pressure psi should be mine is 45 psi it is also unlikely that it is jet pump 155,000 miles and still love my x if any one can weigh in with a guess hunch anything im all ears thank you all ps ill never stop searching for this solution

 

xxxjag, according to the JTIS, the fuel system should be maintaining the fuel rail at about 55 psi (380 KPa) across the injectors. So, you should be reading about 45 psi with the engine running and the pressure rise slightly as you get on the gas hard (ie, lower the vacuum in the intake). If you can, keep the fuel pressure gauge connected as you are going down the road. That way you can keep an eye on the fuel pressure and see what happens. If you see the pressure drop, then you know there is an issue with either the computer not sending the correct voltage to the fuel pump or the fuel pump is starting to go and it can't pump enough for what the car needs.

 

Thermo thanks for your infinate wisdom after your advise i am pretty sure that i should get into the fuel pump line with the high mileage and all i think if i was getting an erratic signal at the pump id get a MIL light will order new pump asap will post my performance results there after ps glad i got a response from you ive read many of your post your like the holy grail of x types talk to ya soon XXX

 

hi,I have a 2005 X type,similar problem,usually runs ok till the car is turned then restarted then it happens like clockwork,starved of fuel.Have replaced the filter then the fuel pump and it still happens.I was wondering if it is the Schrader valve on the fuel rail.I talked to the me ha nice who did the fuel pump for me and he said it only returns excess fuel back to the tank.I was wondering if this valve opened too soon would it reduce the pressure to the injectors causing the problem?

 

9 year old thread, beginning a new one would probably been more advisable. And being a 2004+ model, the under hood schreader valve should have been eliminated.

X Type have returnless fuel systems.

Jaguar explanation =

continuing the drive for fuel consumption benefits, a new fuel system including fuel tank, fuel pump, pipes, breather pipes has been installed.

The X-Type now benefits from the use of the return-less fuel delivery.

The fuel pump uses the principle of operation where the ECM monitors differential pressure across the fuel injectors and the injector pulse width and duration to accurately calculate the fuel quantity being delivered to the cylinders. It uses this to demand a specific fuel flow rate, which it communicates to a fuel pump driver module.

The ECM use a frequency of 150 Hz (PWM) signal during average conditions, varying its
duty cycle between 4 and 50% to control fuel delivery rate or turning it to 75% to turn off the pump.

 

Greetings to everybody,

My car is X-Type 2.1L petrol auto. Could you please enlighten me a bit. I'm getting 65-67psi of fuel pressure no matter what and the car is running rich all the times. Please check on the photo. I suspect the fuel pressure regulator is faulty and the fuel rail part on the second picture is the fuel pressure regulator (?). Do you have any idea what may cause this high fuel pressure ? Should I try to replace it ?

Regards
Spyros

#1 - Fuel pressure at idle or open throttle is the same


Fuel rail Part. Is this the regulator?

 

No, your system is doing fine !

The 2.1 litre engine fuel system is totally different to that of the bigger engines. It's design pressure is 4.5bar/65psi and is controlled by an integral mechanical regulator in the fuel pump in the tank
Your photo is of the pressure pulse damper.

 

Many thanks astromorg.