Our 1996 XJ6 (US Model) has an intermittent fuel supply problem. The car acts like it is out of gas, but after resting for a few minutes it will start up and run for a few more minutes. Prior to the engine dying the car bucks, hesitates and then quits.We have replaced the fuel pump and high pressure submersible fuel hose supply hose in the the tank but problem still persists. Car acts like it has no gas but the tank is half full.
We are wondering if it is the fuel pressure regulator or air mass (flow ) meter. Any advice would be apprreciated.
Thnaks, Bill McLin

 

Did you change the fuel filter?

 

Sorry but you've have actually posted in the wrong subforum. This one [Edit: before it was moved] is for the XJ 2003-2009, ie the X350 and X358.

Your car, if it's 1996, is an X300 and there's different subforum for that.

 

Thanks for redirection!

 

Our 1996 XJ6 (US Model) has an intermittent fuel supply problem. The car acts like it is out of gas, but after resting for a few minutes it will start up and run for a few more minutes. Prior to the engine dying the car bucks, hesitates and then quits.We have replaced the fuel pump and high pressure submersible fuel hose supply hose in the the tank but problem still persists. Car acts like it has no gas but the tank is half full.
We are wondering if it is the fuel pressure regulator or air mass (flow ) meter. Any advice would be appreciated.
Thanks, Bill McLin

 

I would replace. swap out, the fuel pump relay. They are documented as getting lazy as they age.

Hindsight, but I always replace that relay when I replace the pump, it just ticks another box.

 

Hi Bill,

I'm glad you found the X300 forum. I have merged your two threads.

The first thing I would recommend is that you have the car scanned for any stored Diagnostic Trouble Codes that may give you some clues as to what is going on. The X300 OBDII system is somewhat primitive, but if any codes are stored they may save you time in resolving this issue.

It's not easy to connect a fuel pressure gauge to an X300 without special adapters, but problems with the fuel pump electrical system wiring are common. It might be helpful to monitor the voltage at the fuel pump relay socket when the problem is occurring to see if the voltage is sagging. One of the common problems is burned wiring in one of the large electrical connectors (PI-1 (white) and PI-61 (black)) near the right headlamp/windshield washer fluid reservoir. The fuel pump circuit also passes through the Ignition Positive Relay in the Left Hand Heelboard Fuse Box.

You can download the wiring schematics here:

Jaguar X300 Electrical Guide 1996

Since problems like yours can be exacerbated by multiple components operating out of spec, how long has it been since you gave the engine a good tune-up? On an AJ16, that includes replacing the spark plugs with the correct Champions, air & fuel filters, cleaning the MAFS, cleaning the throttle body and Idle Air Control Valve, cleaning the gunk out of the air intake, cleaning the grounds in the engine bay including the engine ground strap, checking the fuel pressure regulator vacuum hose for wet fuel, adding a bottle of fuel injector cleaner to the fuel tank, etc. Other worthwhile preemptive steps are to replace the Engine Coolant Temperature Sensor (ECTS) and the Crankshaft Position Sensor (CKPS) since they both fail with age and can cause difficult-to-diagnose gremlins.

Please let us know if you find any codes when you have the car scanned and we'll try to help.

Cheers,

Don

 

I would explore the relay as described above, and if no joy, take a look at the fuel pressure regulator, which is easily accessible in the engine bay.