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step on gas, a pause, then surge away

 
Old 08-26-2016, 12:58 AM
  #1  
Edward 96 Viper GTS
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Default step on gas, a pause, then surge away

2006 CSti. 104k miles. when starting from a stand still, car will pause at initial throttle tip in, the jack rabbit away. quite annoying.
any ideas on problem and fix?
coils done 30-40k miles ago.
tia,
ed
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Old 08-26-2016, 01:19 PM
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Petza914
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Put it in Sport mode or click the Tiptronic button down once before taking off. In Normal mode, it starts in 2nd gear, which I hate. First thing I do when I get in and start the car is press the Sport button, then click the suspension button for normal, then click the ride height button up back to normal. I find this to be the best combination as it makes the auto shifting better (faster) and makes the car start in 1st gear from a stop instead of 2nd.
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Old 08-26-2016, 02:47 PM
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Seems to be just one of the common issues with the Cayenne. I've found mine does it when I'm applying the brake and begin throttling up like when trying to pull out into traffic. Terrible time for it to do it. I've read where a computer flash update helps. Can't stomach the thought of paying a dealer to provide what should be free so I just pay attention and keep my foot off the brake a couple seconds before pulling out. Would of thought it would be a safety recall. There are several threads out there on the issue. Good luck.
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Old 08-29-2016, 09:36 PM
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Sniffer
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What gear are you in when it hesitates from stop?

Mine does similar and its most noticeable in first - is that normal?
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Old 08-30-2016, 09:22 AM
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There was a TSB released some time ago about a software update to remedy this. If you need to stand on the brake to get the car to accelerate smoothly, you definitely have an issue. Our 04 CTT accelerates like any other car from a stop, even in 2nd gear. If I need to make a getaway, click down to first, or smash my foot into the kick down button. Otherwise, I find starting off in 2nd just fine for the downtime driving that we mostly do.

The trans will learn your driving style, and for most people, that means learning to short shift into an RPM range where there is essentially no throttle response due to turbo lag. The trans, IMO, also fails to downshift fast enough when I put in a high-load request unless I hit the kick down or really put my foot deep into the gas pedal. PSM off or manually shifting fixes this as the car will hold the gears higher in the RPM range where throttle response is better. But, those are the only two things I notice about the shifting behavior with this car that really annoy me.

The minute the gas pedal starts moving from a stop, the car starts moving. Throttle response feels as good as any other turbo car.
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Old 08-30-2016, 12:44 PM
  #6  
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I'm noticed a simular issue but only when I'm below a 1/4 of a tank. Yesterday I was noticing slow pick up from a red light, to the point that I put it in sport mode to get it to drop into first gear. I was also low on fuel, stopped by my shell station, filled up and boom, no more acceleration issues. This is the first time I'm put two and two together, but I will monitor the issue. I wonder if this isn't the first signs of a fuel pump failure ??
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Old 08-30-2016, 01:23 PM
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J'sWorld
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A couple things I will throw out there about the Cayenne that some may not know.

If you are rolling and on the gas then apply the brake while still on the accelerator, the ecu will close the throttle abruptly. If you are at a stop and holding the brake then switch to the accelerator too fast, the same feature will cause a delay in the throttle opening. There was a TSB about this where the coding was changed to decrease the delay time as customers were complaining. This can also be coded out entirely, I think its refereed to as "left foot braking" and applies to automatics. Removing it entirely would be the job of a tuner and the dealer will not do this.

Concerning downshifts- if you stab the accelerator pedal twice in quick succession the transmission will drop 2 gears instead of one. The reaction time using this method is even faster than putting the accelerator to the floor and getting the downshifts you need. I could be wrong but this is because when you do the former the TCU understands you are requesting two shifts down and completes the request immediatly. When doing the latter the immediate protocol is to shift down once and then the ECU has to look at torque requested by driver, realize that this is not possible with current rpm/throttle angle/gear, and then send a message to the throttle to close momentarily while an additional downshift or more is completed, send a msg to the transmission to complete the downshift(s), and re apply the throttle.

Last edited by J'sWorld; 08-30-2016 at 01:30 PM. Reason: adds
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Old 08-30-2016, 03:17 PM
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I thought it was the other way around. Double stab shifts once, kick down shifts to lowest gear available (limited by RPM).

I think the trans itself shifts are pretty quick, it's the programing that sucks. I'm really surprised nobody has come out with a TIP chip for this thing. I'd happily pay a grand for one over an ECU tune.
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Old 08-30-2016, 04:21 PM
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J'sWorld
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Double tap downshift is in the owners manual I believe. I agree the programming leaves some things to be desired. What Id really like to know is EXACTLY what the transgo« mods do on mechanical level to the valvebody and if they circumvent the programming shortfalls.
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Old 08-30-2016, 08:28 PM
  #10  
PhilT3 (PT3)
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Would be great if the PDK-S was available in the Cayenne!
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Old 08-31-2016, 05:54 AM
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There was some talk about a Cayenne Tip chip on 6speed but not much has happened in over a year.
http://www.6speedonline.com/forums/c...port-here.html
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Old 08-31-2016, 05:22 PM
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J'sWorld
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I found this a while back and someone should try it.







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Old 08-31-2016, 10:33 PM
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Good info Mr Haney, Thanks.
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