Jaguar XK-Series Engine Problems

Mr_Shiftright

Some XK owners report engine hesitation, stuttering and other symptoms of erratic engine operation. Have you had these experiences and solved them, or are you having them now?

charlie193

From new, my 1998 XK8's engine (now 67000 miles) stutters at light acceleration, abt 2200 to 2800 rpm, as when climbing a mild hill or accelerating on a freeway ramp. Jag dlrs check with their computer and tell me 'all is OK', but stuttering persists. When it starts stuttering, heavier throttle eliminates the problem. Other Jag owners tell of the same problem. Symptom seems similar to some other fuel injected engines whose software mapping has errors, surging up and down on power at abt half-second intervals, repeatedly until out of that power band. With a long mild hill, it will persist. Any corrective action available?

charlie193

I had previously reported a stuttering problem from day one with my1998 XK8, as when climbing an urban long mild hill. Abt 1300-1400 rpm in top gear under load the engine would stutter badly. Heavier throttle would get out of the condition. Dlrs all across the US expressed ignorance and could not duplicate. I found a very capable Jag tech who understood exactly my problem and reprogrammed the Engine Control Computer, which cured the problem. I was told that my car (020160) is in the VIN range wherein the problem exists. Problem solved.
Charlie, Seattle

svp

My 2000 XK8 has a strange problem. 4 or 5 times a year, the car stalls while moving and then will not start. No clicking, no grinding, just nothing. But all the electrical stuff goes nuts -- steering wheel telescoping repeatedly, gas latch poping open, trunk and hood lids popping open. If I tow it home & let it sit for a couple of days, it starts again. It's been to the dealership several times. They said it was the gearbox & changed that. No help. Now they say they cannot find any problem. Does anybody know what is going on with this car? Thanks.

Mr_Shiftright

The gearbox? That's a weird diagnosis!

Anyway, this sounds like a computer problem..a total misfire...I just can't think of any other component that has control of that many functions all at once. I mean, no one fuse or relay could kill the ignition and work the trunk!

One would have to examine the wiring diagram carefully to understand how this all fits together.

rshoemaker

Can you tell me the mechanic who reprogrammed your computer to take care of the stutter? I have a 1998 SK8 with the same problem and live here at Lake Tapps outside of Auburn.

theflyer

I just bought a 2003 XKR (9000 miles) with this stuttering problem. Worse case at 1200-1500 RPM in any gear but more pronounced when on a slight incline or flat road. Two dealers (and $ 3000.00) with no luck. This car also shifts very hard compared to my 1998 XJR that runs beautifully.

Anybody no of a dealer who knows how to fix this ? The car is of little use running the way it does.

john3880

I HAVE A 1997 XK8 THAT WILL CRANK OVER STRONG BUT NOT START DOESN'T SOUND LIKE IT IS FIRING JUST A HIGH PITCH WHINE, IT HAS BEEN SITTING FOR @ 2 WEEKS.

gene37

There have been several forums concerning 1992 XJ6 starting problems, apparently engine not getting fuel. Lots of discussions and theories--but can anyone provide the "bottom line" on this question. My 92 has decided not to start; except on occasion it will finally start when the battery is almost gone. Runs good after starting, but after sitting overnight--no go. Any help??? Gene37

Mr_Shiftright

sounds like the symptoms of a bad fuel pressure regulator. You can test these by pulling off the vacuum line that operates the diaphragm inside the regulator. If fuel dribbles out, the regulator is toast.

With a bad fuel pressure regulator, no pressure is maintained in the fuel rail overnight, requiring the fuel pump to pump fuel all the way from the gas tank, to repressurize the fuel rail and then start the car--in other words, the defective regulator bleeds off pressure overnight but not during the day.