V8v sticking accelerator
Discussion
So my car tried to kill me tonight. Accelerating before letting off or a corner and the car continues to accelerate. Had to dip the clutch and watch the revs rise. Few taps on the accelerator pedal and the revs dropped.
Anyone have ths happen?
Any advice? Looks like I'll be calling out AA tomorrow.
Anyone have ths happen?
Any advice? Looks like I'll be calling out AA tomorrow.
Sounds sort of familiar. Have you looked at http://www.pistonheads.com/gassing/topic.asp?h=0&a...
oh dear...you are not having much luck with it 
an OBD II reader is a useful accessory too, to save trips to dealer etc just for a light, and to put your mind at rest there really isnt anything wrong. You can write down the codes, reset and see if they come back etc
most are nothing major, a 15 wheel speed sensor wire needing replacing can cause chaos with the ABS/TC warning lighting up
an OBD II reader is a useful accessory too, to save trips to dealer etc just for a light, and to put your mind at rest there really isnt anything wrong. You can write down the codes, reset and see if they come back etc
most are nothing major, a 15 wheel speed sensor wire needing replacing can cause chaos with the ABS/TC warning lighting up
Edited by bogie on Sunday 18th March 15:13
No need for me to start a thread then - this is exactly the syptoms I am getting. Throttle body clean has done nothing (but still needed a clean). Do you have Cruise fitted Gareth? I got the plethora of errors, that cleared on restarting engine on one occasion, other than that, no errors on the dash.
Symptoms present when:
Car moving, can not replicate revving from stationary.
Very intermittant, often at start of a journey (first 5 miles) then been fine.
Dropping engine speed below <10mph with low revs stops it happening, although can re-occur.
This makes me think:
1) It's not the throttle pedal, or would do it when stationary?
2) It's not the throttle bodies - or it would do it when stationary?
3) Could be a cruise control issue as presents when moving over a certain speed
4) I don't know enough!
Yet to try:
1) Removing fuse for cruise (if there is a distinct one) and seeing if that helps
2) Seeing if a hard / soft battery reset helps
I've scanned AMOC and found nothing relevant, does anyone else have any ideas? My experience hasn't been as extreme as Gareths, but it's not fun. My next step will be to call Bamford Rose / Trinity to see if either of them have come across this before getting the car to one of them.
Cheers all
Kris
Symptoms present when:
Car moving, can not replicate revving from stationary.
Very intermittant, often at start of a journey (first 5 miles) then been fine.
Dropping engine speed below <10mph with low revs stops it happening, although can re-occur.
This makes me think:
1) It's not the throttle pedal, or would do it when stationary?
2) It's not the throttle bodies - or it would do it when stationary?
3) Could be a cruise control issue as presents when moving over a certain speed
4) I don't know enough!
Yet to try:
1) Removing fuse for cruise (if there is a distinct one) and seeing if that helps
2) Seeing if a hard / soft battery reset helps
I've scanned AMOC and found nothing relevant, does anyone else have any ideas? My experience hasn't been as extreme as Gareths, but it's not fun. My next step will be to call Bamford Rose / Trinity to see if either of them have come across this before getting the car to one of them.
Cheers all
Kris
I wouldn't discount the sticking throttle body. If the engine is not under load (like when in neutral) then the ECU won't open the throttle much. It may be indeed be that it is sticking, but not at an angle that it can reach when not under load. If you have an OBD2 scanner with realtime measuring facility then you should be able to see what the throttle valve angle is under different conditions and this may help you determine whether the sticking occurs at a certain aperture.
BingoBob said:
I wouldn't discount the sticking throttle body. If the engine is not under load (like when in neutral) then the ECU won't open the throttle much. It may be indeed be that it is sticking, but not at an angle that it can reach when not under load. If you have an OBD2 scanner with realtime measuring facility then you should be able to see what the throttle valve angle is under different conditions and this may help you determine whether the sticking occurs at a certain aperture.
Thanks Bob, that is not a bad thought, I really don't know enough 
When the engine parameters change outside of normal ranges (say the throttle sticking open) that messes with the ECU's ability to calculate engine torque values.
The ECU passes these torques values (amongst other things) to the ABS / ESP brain which needs that information to calculate, er, things.
Anyway, if the ABS / ESP module gets dodgy information then it can't do its job and it lights up the dash to tell you so.
Might not be that, of course, but it kinda fits.
The ECU passes these torques values (amongst other things) to the ABS / ESP brain which needs that information to calculate, er, things.
Anyway, if the ABS / ESP module gets dodgy information then it can't do its job and it lights up the dash to tell you so.
Might not be that, of course, but it kinda fits.
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