I was humming along on the freeway this evening around 65 MPH in my 2000 XJR when all of a sudden, no power. I depressed the gas pedal, nothing. I looked at the dash and "Restricted Performance" message was displayed. All the while, I can barely keep the car going fast enough to get over to the right shoulder. I was nearly run down by a semi car hauler. In the end, I was able to limp it over to the right shoulder not before getting flipped off by several drivers even though I had my flashers on. The computer decided that saving the engine was more important than my life.


How in God's name can any developer write code into the computer that puts the car in limp mode and operating at only idle? Okay, what if this happened while I was making a left turn? Would I be able to idle it thru the intersection before being hit head-on by an on-coming driver? I would expect that in this mode you should be able to operate the vehicle at a safe enough speed to not be killed. In this limp mode state, I was barely able to go faster than 5 MPH at idle with no response from the gas pedal. I genuinely feared for my life.


Is there anyone out there that has experienced the same type of scenario? Is there a way to alter the speed of the limp mode or even disable the limp mode altogether. I don't care if the engine blows up to save my life!!!! Sorry XJR, I value my life more than yours!


BTW, after getting over to the right shoulder, I turned off the car and restarted it and it was running just fine like nothing happened. Good thing it went into limp mode!!!


I will run a scan to see if there are any stored codes.

 

If the engine blew up it wouldn't even do 5mph.

 

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then give ASI a call and get your throttle body rebuilt. The best way to deal with limp home mode is to fix the actual problem, not the safety measures built into the ecu that are designed to prevent catastrophic failures

 

You guys are missing the point. I did not have any indications that any trouble was about to arise before this happened. I have not had any SES lights come on for years, no other indications that a problem was about to occur. The car was running perfectly before and after the incident. BTW, no SES light after this incident, and no, the bulb is not burned out.

I agree that the problem should be fixed whatever it may end up being, but limp mode should not be at engine idle. That in it's self is is very dangerous to the driver. I should be able to safely manuver the vehicle out of harms way.

I am not looking for sympathy here. I need to know if my limp mode is programmed corectly. If not (which is what I think) I would like to have it repaired.

If you do not agree with the safety issue, please do not comment.

Thanks,

 

With normally aspirated engines limp mode puts the transmission into 4th gear but does limit the engine to idle rpms, and I doubt the SC engine is different. It sounds like a throttle body problem, possibly the tps.

 

Your limp home mode is working perfectly fine. It limits gear selection and throttle to allow you to... take a guess... limp home

PS you've perfectly described an unexpected failure. Claiming you should have had some kind of 'warning' seems a little presumptuous.

Have you had the fault codes scanned yet? TPS failure is notorious for not showing up as a fault code until it becomes a regular occurrence, which in some cases (like mine) can take around 6 months. It's not always an easy fault to replicate, but usually happens when you're off throttle. A fun example is just after you've floored it to pass someone, then lose your throttle
I wouldn't be too worried about getting run down while making a left hand turn. Going into fault mode while on the gas is very rare, it's once you take your foot off that's the problem.

Best of luck with diagnosing and resolving your issue though. Nobody likes hearing of broken cats, but maybe give it more than 30 minutes before coming on here to rant next time

 

Doug - I feel your pain! Driving the freeways in Southern California is challenging enough, but even more so when you suddenly lose power by going into restricted performance mode - and it happens in traffic at speed.

As mentioned above, I would also suggest you call ASI, and get the Throttle Body rebuilt. That will most likely solve the problem; it did on my car.

Good luck!

 

The OP does have a point.

Put up a blaring horn, flashing red lights, whatever. But, in the end
the driver ought to have the choice of whether he wants to continue
on with his choice unimpeded or at least have an emergency override.

It certainly was possible in vehicles preceding the X308.

Restricted performance might save an engine from sure destruction,
but I have a suspicion that the prime benefactor during warranty
coverage was Jaguar, not the owner.

And developers? Most of them work in a mental vacuum.

Something that never occurred to them: override restricted
performance if the the four way hazards are turned on.
Simple and easy.

++

 

I have a 2005 xj8l with 130k miles. I have been having the same problem, but with other symptoms. My low engine coolant light is coming on, but the coolant is not low, transmission is slipping in first gear and the battery seem to die and not want to start in the morning. All started at about the same time. Any help would be appreciated.

 

cmarriaga-
You will get better results if you post in the "X350" forum, which is the modelof your car, assuming the 2005 is not a typo. But, I will give you my $.02 anyway... your issues are seemingly unrelated except that they al "started about the same time" and it sounds like you need to just work through each of them individually. There is some possibility some symptoms are related to the low battery voltage, so I suggest you start there. Like maybe "have the battery tested".

 

69ra3ta - Rather than post on here, find the person in Jaguar UK who heads up technical/engineering and write a letter with envelope marked with their real name and Private & Confidential, saying what you think ought to be done - an override or whatever.

You likely have road/transport safety authorities in USA so write to them as well.

Anything you say on here is not going to be read by those who count.

 

69ra3ta-
So you post a mild rant then ask that only those who agree comment??
I happen to agree completely with your point, but that ain't the way a FORUM works, bro!

 

At least not this forum. We learn from each other and the multitude drives out bad information (and occasionally bad performers). For the better maybe, since 1990s, cars have been managed by digital systems, not mechanical and analog. digital is still yes or no. The car says it is broken or violating California law so you get restrictions.