Engine high revs in "park"
#1
Engine high revs in "park"
I have a 2010 supercharged XKR Jaguar sports car which I bought new ten years ago. I also owned an earlier version of the Jaguar sports car from 2000 to 2010. Just to put the standard responses to rest I have never "big footed" either of these cars (or any other cars) over many years of driving. I do plead guilty to the second standard response that I am 81 years old but I am physically fit and mentally alert for a person this age. I am interested in responses that might relate to other people having the same technical problem.
Now, let's get to the problem. One morning I enter the car, step on the brake, and push the start button. The car is in "park". The engine revs at a high rate of speed for one second and then drops immediately to normal idle speed. I am surprised but because the engine is at idle speed I back out of the garage. I drive to my appointment and back home and the car acts normally. The next day I drive the car and the car acts normally.
The third day I start the car normally and drive to a gas station. After filling up the car with high octane fuel, I get in the car and when I start it, the engine goes into high rev for a second and drops immediately down to normal idle speed. So far I have not touched the accelerator with my foot. I simply rotate the shift knob into drive. The engine instantly goes into maximum rev without me touching my foot to the gas peddle. In shock, I stand on the brake with unknown results. The car is stopped by a post 15 feet in front of me. I turn off the car, talk to the station manager, then restart the car and it sounds normal so I drive home. Upon arriving home I restart the car twenty times to see if I can recreate the high rev situation. The car acts fine.
Has anyone else had the situation of their Jaguar engine going into high rev when in the "park" mode or after shifting to "drive"? I would greatly appreciate any advice I can get!!
Steve Moksnes
Now, let's get to the problem. One morning I enter the car, step on the brake, and push the start button. The car is in "park". The engine revs at a high rate of speed for one second and then drops immediately to normal idle speed. I am surprised but because the engine is at idle speed I back out of the garage. I drive to my appointment and back home and the car acts normally. The next day I drive the car and the car acts normally.
The third day I start the car normally and drive to a gas station. After filling up the car with high octane fuel, I get in the car and when I start it, the engine goes into high rev for a second and drops immediately down to normal idle speed. So far I have not touched the accelerator with my foot. I simply rotate the shift knob into drive. The engine instantly goes into maximum rev without me touching my foot to the gas peddle. In shock, I stand on the brake with unknown results. The car is stopped by a post 15 feet in front of me. I turn off the car, talk to the station manager, then restart the car and it sounds normal so I drive home. Upon arriving home I restart the car twenty times to see if I can recreate the high rev situation. The car acts fine.
Has anyone else had the situation of their Jaguar engine going into high rev when in the "park" mode or after shifting to "drive"? I would greatly appreciate any advice I can get!!
Steve Moksnes
Last edited by GGG; 01-03-2021 at 06:35 AM. Reason: Remove email address
Top Answer
01-15-2021, 09:52 AM
Acceleration on cold start solved
I went through the NHTSA acceleration complaints for 07-10 Xk's.
SNIP
Vid link attached, from this morning. Relevant start at .15, goes to 1.05 when I cut it off at 3K this time.
Except for the brief brake pedal to start it, my feet are nowhere near either pedal. This was immediately after a hard reset, but has been occuring every time the engine is completely cold.
My foot goes nowhere near the accelerator. No codes are thrown.
In the vid's final start, the car behaves completely normally.
Snip
SNIP
Vid link attached, from this morning. Relevant start at .15, goes to 1.05 when I cut it off at 3K this time.
Except for the brief brake pedal to start it, my feet are nowhere near either pedal. This was immediately after a hard reset, but has been occuring every time the engine is completely cold.
My foot goes nowhere near the accelerator. No codes are thrown.
In the vid's final start, the car behaves completely normally.
Snip
Cold start now increases to an acceptable 1200-1500, with expected drop to normal idle.
Also identified one vacuum leak with a smoke test at the base of the oil filler tube, and part on order. The o-ring is likely rotted.
Plan is to fix this obvious one, then run a more aggressive smoke test at a higher pressure to get others.
Just a comment: I'm finding a lot of useful info on the X100 boards. Lots of engine things that appear on 15-20 year old X100's, such as vacuum leaks and degrading sensors will also appear on the relevant X150's as they age. Good place to look for ideas.
Best, Panthera
Last edited by panthera999; 01-15-2021 at 10:19 AM.
#2
#3
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Steve - I don’t have an answer for you, but wanted to thank you for such a well written description of the problem.
It should ward off the naysayers that jump in on ‘sudden acceleration’ issues and say it was operator error, foot on both the brake and gas at the same time, gas pedal stuck in a floor mat, etc.
It should ward off the naysayers that jump in on ‘sudden acceleration’ issues and say it was operator error, foot on both the brake and gas at the same time, gas pedal stuck in a floor mat, etc.
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Steve Moksnes (01-07-2021)
#4
Given how thoughtful you are, you've probably thought of this but...as a work-around until the problem is fixed, apply maximum braking every time you shift out of park.
Also, has this happened when shifting into reverse from park?
#5
The gas and brake pedals on my XKR are very close to each other, and it is possible to accidentally depress both simultaneously. I inadvertently did this once, years ago and it was scary! The harder I pressed on the brake, the faster the car revved up (until I realized what I did). Fortunately, no harm done.
If you depress the brake pedal hard with the left half of your right foot on the right corner of the brake pedal, the right side of the sole of your shoe will contact the gas pedal and cause unintended acceleration. That's a real problem if your shoe size is 11EEE!
Remember to always center your right foot on the brake pedal so you don't inadvertently press the gas pedal.
This close-pedal design probably goes back to the days when Jags had manual trannys and racers used the heel-toe technique while downshifting. The pedals on my wife's MDX are much farther apart.
You can also avoid this problem simply by pressing the START button first, before you step on the brake pedal. All you need is a light tap on the brake and it'll start right up. Yes, I know that's the opposite of what the Owner's Handbook says, but trust me, it works.
If you depress the brake pedal hard with the left half of your right foot on the right corner of the brake pedal, the right side of the sole of your shoe will contact the gas pedal and cause unintended acceleration. That's a real problem if your shoe size is 11EEE!
Remember to always center your right foot on the brake pedal so you don't inadvertently press the gas pedal.
This close-pedal design probably goes back to the days when Jags had manual trannys and racers used the heel-toe technique while downshifting. The pedals on my wife's MDX are much farther apart.
You can also avoid this problem simply by pressing the START button first, before you step on the brake pedal. All you need is a light tap on the brake and it'll start right up. Yes, I know that's the opposite of what the Owner's Handbook says, but trust me, it works.
#6
#7
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Tervuren (01-03-2021)
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#8
The Jaguar X150 uses an electronic "drive-by-wire" system to control the throttle (gas pedal) position. There is no mechanical linkage between the gas pedal and the engine, and various electronic sensors enable the ECU to determine fuel delivery. That system includes safeguards to prevent unintended, sudden acceleration.
Is X150 sudden acceleration possible without driver error? I haven't found any credible evidence to support a "Yes" answer, so my answer is "Probably not."
See:
https://www.jaguarforums.com/forum/x...ration-182227/
https://ieeexplore.ieee.org/document/639984
"Abstract:The electronic throttle is a major innovation of the AJV8 engine in the Jaguar XK8 vehicle. Although essentially transparent to the driver, it moves Jaguar into new territory, and has often been referred to in the past as "drive-by-wire". Jaguar, in partnership with the Denso Corporation, has developed a system that while still offering a simple mechanical solution to assuring overall safety, also recognises the importance of the increased criticality placed on computer controls. This paper discusses both the system safety concepts, and describes the state-of-the-art methods that have been used throughout the development of the XK8."
See also:
https://en.m.wikipedia.org/wiki/Sudd...d_acceleration
Is X150 sudden acceleration possible without driver error? I haven't found any credible evidence to support a "Yes" answer, so my answer is "Probably not."
See:
https://www.jaguarforums.com/forum/x...ration-182227/
https://ieeexplore.ieee.org/document/639984
"Abstract:The electronic throttle is a major innovation of the AJV8 engine in the Jaguar XK8 vehicle. Although essentially transparent to the driver, it moves Jaguar into new territory, and has often been referred to in the past as "drive-by-wire". Jaguar, in partnership with the Denso Corporation, has developed a system that while still offering a simple mechanical solution to assuring overall safety, also recognises the importance of the increased criticality placed on computer controls. This paper discusses both the system safety concepts, and describes the state-of-the-art methods that have been used throughout the development of the XK8."
See also:
https://en.m.wikipedia.org/wiki/Sudd...d_acceleration
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Tervuren (01-03-2021)
#9
I have also on three or four occqsions pressed the brake pedal and the edge of my gas pedal while in drive, and it scared the hell out of me, especially since when it happens you don't realize your foot is on the gas so you keep pressing the brake harder which, in turn, presses the gas pedal harder before you understand what you've done. But the OP seems to have a different problem probably related to the fuel injection system.
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Tervuren (01-03-2021)
#10
I have to agree on both counts. Sorry to hear about your "event" at the gas station. I've not experienced your problem yet - and hope not to.
Given how thoughtful you are, you've probably thought of this but...as a work-around until the problem is fixed, apply maximum braking every time you shift out of park.
Also, has this happened when shifting into reverse from park?
Given how thoughtful you are, you've probably thought of this but...as a work-around until the problem is fixed, apply maximum braking every time you shift out of park.
Also, has this happened when shifting into reverse from park?
#11
Welcome Steve, 10 years original owner, that is a rarity on this board!!!
This same issue has been reported in the past, most responses like you see so far have always focused on operator error which has validity. I don't know that it was ever resolved by the previous complainants, but in one instance a person reported the issue was fixed with a software update by the dealer, the link below will start you at the relevant Post #26 by Robert Page. Feel free to scroll the rest of the thread also:
Sudden acceleration !! - Page 2 - Jaguar Forums - Jaguar Enthusiasts Forum
This same issue has been reported in the past, most responses like you see so far have always focused on operator error which has validity. I don't know that it was ever resolved by the previous complainants, but in one instance a person reported the issue was fixed with a software update by the dealer, the link below will start you at the relevant Post #26 by Robert Page. Feel free to scroll the rest of the thread also:
Sudden acceleration !! - Page 2 - Jaguar Forums - Jaguar Enthusiasts Forum
Last edited by tampamark; 01-03-2021 at 05:11 PM.
#12
Just something to try from here out.
Use your left foot on the brake to start the car with it on the left side of the pedal.
I also find that what Stuart suggested of hitting the start button then the brake pedal seems to be how the car was programmed to work.
This, despite it saying the oppisite in the manual.
Liekly whoever wrote the manual and whoever programmed that aspect of the car last didn't get in touch in time.
Use your left foot on the brake to start the car with it on the left side of the pedal.
I also find that what Stuart suggested of hitting the start button then the brake pedal seems to be how the car was programmed to work.
This, despite it saying the oppisite in the manual.
Liekly whoever wrote the manual and whoever programmed that aspect of the car last didn't get in touch in time.
#13
The reason responses immediately go to "foot on gas and brake" is the situation is happening at a moment of intended pressure from a foot.
And it isn't just age, younger people can do it to.
I did it in my Corvette, was wearing a pair of hiking boots I'd never worn to drive that car.
They were just that much wider.
And it isn't just age, younger people can do it to.
I did it in my Corvette, was wearing a pair of hiking boots I'd never worn to drive that car.
They were just that much wider.
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35olds (01-07-2021)
#14
#15
If you didn't intend to post here, then you're probably a victim of "Infinite Scroll", a feature that many Forum members dislike.
#16
As mentioned above, the throttle is "fly-by-wire". It therefore can't be a mechanical issue where a cable is sticking. This leaves two plausible options:
1. a fault with the APP (Accelerator Pedal Position) sensor
2. fault in the throttle actuator control - jammed throttle blade, gearing or motor circuit
To progress with this you need to run a SDD diagnostics session for relevant DTC's.
Graham
1. a fault with the APP (Accelerator Pedal Position) sensor
2. fault in the throttle actuator control - jammed throttle blade, gearing or motor circuit
To progress with this you need to run a SDD diagnostics session for relevant DTC's.
Graham
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Stuart S (01-03-2021)
#17
It appears that there have been no recalls or Technical Service Bulletins affecting 2007 X150 models for sudden or unintended acceleration. There was 1 report of unintended acceleration while braking. See:
https://www.nhtsa.gov/vehicle/2007/J...2%252520DR/RWD
https://www.nhtsa.gov/vehicle/2007/J...2%252520DR/RWD
#19
Hi Steve,
My Post #15, above, was in reply to a post by larry minor, whose Public Profile shows that he has a 2000 XK8.
I know that you have a 2010 XKR, which you clearly stated when you started this thread You also explained that you sold your XK8 and that you never "big footed" either one in order to put that possible cause to rest. Nevertheless, my experience and the experiences of others suggest otherwise.
Sudden, inadvertent acceleration by definition means that you're unaware of the cause, including that you might not realize that you did it. Try to be open to that possibility.
Have you tried my "press the START button first" recommendation in Post #7, above? If so, and you still experience the same sudden acceleration, then follow Graham's advice in his post #16, above.
Otherwise, blame your shoe.
Stuart
My Post #15, above, was in reply to a post by larry minor, whose Public Profile shows that he has a 2000 XK8.
I know that you have a 2010 XKR, which you clearly stated when you started this thread You also explained that you sold your XK8 and that you never "big footed" either one in order to put that possible cause to rest. Nevertheless, my experience and the experiences of others suggest otherwise.
Sudden, inadvertent acceleration by definition means that you're unaware of the cause, including that you might not realize that you did it. Try to be open to that possibility.
Have you tried my "press the START button first" recommendation in Post #7, above? If so, and you still experience the same sudden acceleration, then follow Graham's advice in his post #16, above.
Otherwise, blame your shoe.
Stuart
#20
Steve,
I'd like to clarify my post #4 in this thread. Rather than edit it, I am posting again to bring it to the top of the thread.
In applying maximum braking, better to use your left foot and keep the right one out of the equation. That way there is much less risk that your right foot will engage both brake and accelerator pedals. Apologies in advance if this is too obvious!
I'd like to clarify my post #4 in this thread. Rather than edit it, I am posting again to bring it to the top of the thread.
In applying maximum braking, better to use your left foot and keep the right one out of the equation. That way there is much less risk that your right foot will engage both brake and accelerator pedals. Apologies in advance if this is too obvious!