Question about 2001 Jaguar XJ8

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Engine Failsafe mode

I just purchased a very nice 2001 XJ8. While driving at highway speed last night the engine cut power to a very low output causing me to make an emergancy turn off the interstate. The warning screen on the dash read "Engine Failsafe Mode - Trans Fault". The vehicle would not go faster than 10mph. I had to pull over and stop. I shut the vehicle off and then started it back up. The warning lights did not come back on and the vehicle returned to normal operation. I was able to drive it at highway speeds again without issue. I am worried tha this will re-occur when I leave this vehicle for my kids to drive. I am in the military and leaving Friday. Any ideas?

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Probably, your ZP HP-series transmission has failed. You didn't mention your car's mileage but failure is common from 60K - 120K miles. The "lifetime" synthetic fluid accumulates metal dust beyond the filter and magnet's ability to capture it, and sudden and catastrophoic failure occurs. Find a good independent shop (check your local Jag club) and they'll replace the transmission for around $6,000. The dealers charge twice that.

The other possibility is failure of the secondary cam chain tensioners. If you hear a clattering sound when you start the car, turn it off immediately and have the car transported to a good Jag shop. They can replace the plastic tensioners with metal ones for around $3,000. (Rough guess.) Make sure they do the same with the plastic primary tensioners and chain guides, and replace the chains. Failure to take this step after you hear the first symptoms will result in engine failure.

Also replace the plastic water pump and thermostat with alloy units.

Sorry for this bad news. I own a 2001 XJR and it is a fabulous car. It's still a Jaguar, though, and you're going to have to put a few thousand into it. Since these cars are selling for next to nothing on the used market ($12,000 for 80,000 miles), I consider preventive maintenance of $5,000 or so to be part of the investment in a world-class sedan.

Posted on Jan 03, 2009

  • Moneygrnjag Jan 05, 2011

    First of all he has a 2001 they changed the plastic chain tensioners in 2000 to the medal 1s so he don't have the plastic 1s. It is his throttle body they all do it I have a 2000xjr without the plastic tensioners and it did the same thing every 300 or so miles turned out to be a throttle body problem it is a Mercedes Benz transmission that is real strong and when it fails u will know so don't listen to this guy up here trying to make u spend 5-6000$ on a 01 jag when that's what it's worth get a new throttle body for 500$ and you will be all set they been trying to get jaguar to recall this issue but they don't want to hear it.



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