Lurching
#61
Moderator !x4
Thats great news Toby
The more I drive it the more differences I notice, the latest being that the transition between decelleration and acceleration is very much smoother now.
Good suggestion on the log book also, I can see that becoming an issue in a couple of years.
Mike
The more I drive it the more differences I notice, the latest being that the transition between decelleration and acceleration is very much smoother now.
Good suggestion on the log book also, I can see that becoming an issue in a couple of years.
Mike
#62
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I had my '03 S serviced yesterday, including a new set of tires (Pirelli Scorpion Zero), throttle & kickdown adjustment and a bunch of other minor repairs.
The car drives much smoother now. Before, from deceleration to acceleration there would be almost a clunk noise from the gearbox. It is about entirely gone.
An interesting thing is while acceleration delay was an issue from the beginning, lurching didn't become an issue until several months later after I bought the car. My dealer did some warranty repair and after I got it back I observed this issue. Dealer didn't know why except they have had it hooked up to the tool.
Yes my car already needs a new set of tire (at 15K miles).. the original Turanza doesn't last very long, and bringing my S to the tracks didn't help.
The car drives much smoother now. Before, from deceleration to acceleration there would be almost a clunk noise from the gearbox. It is about entirely gone.
An interesting thing is while acceleration delay was an issue from the beginning, lurching didn't become an issue until several months later after I bought the car. My dealer did some warranty repair and after I got it back I observed this issue. Dealer didn't know why except they have had it hooked up to the tool.
Yes my car already needs a new set of tire (at 15K miles).. the original Turanza doesn't last very long, and bringing my S to the tracks didn't help.
#65
Sorry, I was talking about the old issue where the car would just not go at all for 3 seconds or so, usually on exiting a curve (but not always) and usually following a downshift to 2 or 3rd (both Tip or manual).
Speculation was that it was related to the e-throttle programming rather than being a mechanical issue.
Is that what you mean by the "cornering thing" or do I have something else to watch out for?
Thanks!
Speculation was that it was related to the e-throttle programming rather than being a mechanical issue.
Is that what you mean by the "cornering thing" or do I have something else to watch out for?
Thanks!
#66
Moderator !x4
Yes Dan thats what I thought you were talking about just wanted to be clear.
The mods I did to the car reduced the problem, and the recent Lurching fix eliminated that issue and vastly improved the drivability of the car, but the last one remains.
I took the master tech out from my dealer and showed him how to reproduce it.
He is in touch with his PCNA rep about it.
I did read something which sounded like a fix was out there, a Tiptronic change someone had had done, not the kickdown one, but lost who had it done.
Its only ever a problem if I am zoning out somewhere, but it does remain.
ON THE OTHER HAND
When the snow was on the ground it did sort of make a little sense to me and partially confirmed a comment made by the head Porsche Manager at the dealer who told me that it was intended to stop torque effects on slippery or loose ground.
I want it fixed tho.
Mike
The mods I did to the car reduced the problem, and the recent Lurching fix eliminated that issue and vastly improved the drivability of the car, but the last one remains.
I took the master tech out from my dealer and showed him how to reproduce it.
He is in touch with his PCNA rep about it.
I did read something which sounded like a fix was out there, a Tiptronic change someone had had done, not the kickdown one, but lost who had it done.
Its only ever a problem if I am zoning out somewhere, but it does remain.
ON THE OTHER HAND
When the snow was on the ground it did sort of make a little sense to me and partially confirmed a comment made by the head Porsche Manager at the dealer who told me that it was intended to stop torque effects on slippery or loose ground.
I want it fixed tho.
Mike
#67
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I heard that same comment about the snow from the vwvortex board. A dealer told a Touareg owner that.
BTW, I have mine back from the dealer now with the fix. It was the DME reprogramming only. It is better. I am not convinced the hesitation is totally gone though. I will need to drive it more. The transmission fix that some have talked about may actually be a documented fix for earlier Cayennes (before 7/03 build). I am still trying to investigate that. I will post more when I know more.
BTW, I have mine back from the dealer now with the fix. It was the DME reprogramming only. It is better. I am not convinced the hesitation is totally gone though. I will need to drive it more. The transmission fix that some have talked about may actually be a documented fix for earlier Cayennes (before 7/03 build). I am still trying to investigate that. I will post more when I know more.
#69
Hey Mike,
>> I took the master tech out from my dealer and showed him how to reproduce it.
So you know the steps to reproduce it? Mind sharing that?
If anything so that I can show the tech, but more importantly if I know more about the cause I can be more prepared to avoid it...
This is a safety issue that Porsche really needs to address in an honest fashion.
Thanks!
>> I took the master tech out from my dealer and showed him how to reproduce it.
So you know the steps to reproduce it? Mind sharing that?
If anything so that I can show the tech, but more importantly if I know more about the cause I can be more prepared to avoid it...
This is a safety issue that Porsche really needs to address in an honest fashion.
Thanks!
#70
Moderator !x4
Hi Dan
OK, Let me see if I can write this down so it makes sense.
If you approach a 90 degree corner at say 50mph with the intent of leaving the other side of the corner at 35mph.
As you hit the corner you brake or bleed off speed to about 25mph to go through, as you emerge from the corner you give it gentle gas to accelerate and it dies on you.
This can be seen if you watch the gear selected indicator, you are in 5 decellerating you might hit 4, but thats what your left with as you emerge from the corner. All of a sudden your in the wrong gear and the torque / weight / accelerator setting get confused.
A split second later the tiptronic "may" decide to downsfift. If you have changed the filters or exhaust you may have enough to power thru.
The car should have downshifted to 2 and there would not have been a problem.
I just took my tech to a neighborhood and did it a few times.
OK, Let me see if I can write this down so it makes sense.
If you approach a 90 degree corner at say 50mph with the intent of leaving the other side of the corner at 35mph.
As you hit the corner you brake or bleed off speed to about 25mph to go through, as you emerge from the corner you give it gentle gas to accelerate and it dies on you.
This can be seen if you watch the gear selected indicator, you are in 5 decellerating you might hit 4, but thats what your left with as you emerge from the corner. All of a sudden your in the wrong gear and the torque / weight / accelerator setting get confused.
A split second later the tiptronic "may" decide to downsfift. If you have changed the filters or exhaust you may have enough to power thru.
The car should have downshifted to 2 and there would not have been a problem.
I just took my tech to a neighborhood and did it a few times.
#71
Ah! Thanks but no, there is more to that.
BTW, I did replace the filters in my CT.
I use the manual mode 100% of the time these days, and I was in 3'rd probably at about 50mph, then on the brakes, down to 2nd looking to exit the 90 degree corner at about 20.
Dead gas pedal for a good 3+ seconds.
So it sure feels like if one shifted a regular car from 1st to 5th at 15mph, that is a good description.
BUT it is not related to the tranny or selected gear, some electronics are kicking in (or out).
And since the time before it happened to me going straight (but changing lanes) it is unlikely that it was some anti-skid thinghy (dry roads, Florida weather).
But thanks, any duplication can help lead to a resolution.
BTW, I did replace the filters in my CT.
I use the manual mode 100% of the time these days, and I was in 3'rd probably at about 50mph, then on the brakes, down to 2nd looking to exit the 90 degree corner at about 20.
Dead gas pedal for a good 3+ seconds.
So it sure feels like if one shifted a regular car from 1st to 5th at 15mph, that is a good description.
BUT it is not related to the tranny or selected gear, some electronics are kicking in (or out).
And since the time before it happened to me going straight (but changing lanes) it is unlikely that it was some anti-skid thinghy (dry roads, Florida weather).
But thanks, any duplication can help lead to a resolution.
#73
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Something I have noticed:
When I'm in d6 (40-55MPH) and I wish to pass quickly... my choice of gear is 4, I try to go to manual then quickly downshift twice to m4.
The trip doesn't allow me out of the d mode. I thought it was a quick excessive torque limiter in the tip (is that understandable?).
When I'm in d6 (40-55MPH) and I wish to pass quickly... my choice of gear is 4, I try to go to manual then quickly downshift twice to m4.
The trip doesn't allow me out of the d mode. I thought it was a quick excessive torque limiter in the tip (is that understandable?).
#74
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I have noticed the hesitation while cornering as well but I am of the opinion that this is just a particular sequence of transmission shifts and throttle positioning that can be duplicated in a straight line. We just notice it when cornering because that's when that sequence occurs most often.
There is a new review of a Cayenne Turbo in Edmunds that mentions the issue: web page
I have made a new post on rennteam on the subject that may be of interest as well: lurching
There is a new review of a Cayenne Turbo in Edmunds that mentions the issue: web page
I have made a new post on rennteam on the subject that may be of interest as well: lurching