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-   -   Turbo Lag - 2004 CTT - what is normal? (https://rennlist.com/forums/cayenne-955-957-2003-2010/883171-turbo-lag-2004-ctt-what-is-normal.html)

bradbeck 07-14-2015 12:42 AM

Turbo Lag - 2004 CTT - what is normal?
 
Hi:

New to the forum and I'm looking at a 2004 CTT with 115k miles. Full service records since new and the second owner bought it two years ago. It is in near mint condition.

Everything looks great. The only thing I noticed was an oil drip "hanging" from the frame about the mid-way point of the driver's door.

The current owner purchased a 3yr extended warranty, which has a year left. Asking price is $16k.

Carfax shows all the maintenance as well as the "regular oil change" symbol. Coolant pipes, coils and Cardan have been already changed as well as the water pump and lower control arm bushings.

Love everything about it, except it feels like the turbo lag is long. Not sure what is normal and thought I'd ask for your experience. What are the options, if any, to reduce the lag? Drove in sport mode, in Drive. I didn't manual shift, so maybe the rpms are too low for what I was expecting. Is the power band in the higher rpms and therefore doesn't have the low-end rpm turbo-thrust? Now, when it kicks in, it screams.

Given it is a twin-turbo, I guess I expected it to spool up faster, though I have seen some reviews on youtube that the turbo lag is the main complaint. Was I just not driving it right?

Thank you!
Brad

AGARubberDuck 07-14-2015 02:53 AM

Drive it with PSM off and you'll be happy. On an 04 the 'sport' mode just makes the dampeners solid, no drivetrain difference. The cayenne is very docile in drive as it starts in 2ND gear. Couple that with commuter driving and the transmission map goes to full-on geezer mode.
Turn PSM off and drive it like you stole it for a little while and it'll be more like you'd expect. For me,at least, tiptronic shifting is a must if I want to have fun.

bradbeck 07-14-2015 03:17 AM

Thanks AGARubberDuck

The person selling it drives about 5 miles each way everyday and I can see that affecting the mapping based on your comments. I will test it again and this time, not bring my wife. I wasn't able to open it up as much as I would have liked.

We commute in a 2013 Audi Q5 2.0 Turbo for reference. I used to own a 2001 MB CLK55 AMG (until my son totalled it) a year ago. Loved the performance of that car.

knfeparty 07-14-2015 06:26 AM

Manual shift to keep it in 2nd or 3rd and get the rpms to 3k or so. In manual mode you can use full throttle in the gear you're in without the car kicking down a gear. This is the best way to feel the boost build. You should see 0,8 bar for a moment before it settles on 0,6 bar and stays there.

wrinkledpants 07-14-2015 09:58 AM


Originally Posted by bradbeck (Post 12429957)
Hi:

New to the forum and I'm looking at a 2004 CTT with 115k miles. Full service records since new and the second owner bought it two years ago. It is in near mint condition.

Everything looks great. The only thing I noticed was an oil drip "hanging" from the frame about the mid-way point of the driver's door.

The current owner purchased a 3yr extended warranty, which has a year left. Asking price is $16k.

Carfax shows all the maintenance as well as the "regular oil change" symbol. Coolant pipes, coils and Cardan have been already changed as well as the water pump and lower control arm bushings.

Love everything about it, except it feels like the turbo lag is long. Not sure what is normal and thought I'd ask for your experience. What are the options, if any, to reduce the lag? Drove in sport mode, in Drive. I didn't manual shift, so maybe the rpms are too low for what I was expecting. Is the power band in the higher rpms and therefore doesn't have the low-end rpm turbo-thrust? Now, when it kicks in, it screams.

Given it is a twin-turbo, I guess I expected it to spool up faster, though I have seen some reviews on youtube that the turbo lag is the main complaint. Was I just not driving it right?

Thank you!
Brad


The engine is a bit laggy compared to other twin turbo setups, but it also makes good power right up to redline, where other cars - the torque starts to fall off. It's kind of the tradeoff you get with any turbo car that's using a non variable vane turbo. Early spool or top-end torque.

The transmission doesn't help this, either. It seems to hold a gear as you start to increase the load much longer than it should. My wife's A4 will kick down as needed fairly quick, but it's like the Cayenne wants to stay in gear forever.

Putting the pedal to the floor will induce kick down to the lowest gear possible. You'll feel the button at the end of the gas pedal stroke. You can also double click the steering wheel shift button to downshift while skipping a gear.

I drive like an old man, and the tranny has learned this behavior, which sucks. Sometimes, I'll come out of a slow sweeper, and it is still in 4th at 1200 RPM when I'm now trying to accelerate pretty fast. I have to remember to manually downshift it coming out of that corner.

knfeparty 07-14-2015 01:50 PM

I feel like posting a video. Maybe I'll make one.

Dilberto 07-14-2015 02:34 PM

Yeah, the CTT needs some orchestral working of the RPMs, and Tiptronic with ESP off. When done right - it's still better than Sequential/Variable Vane turbos.

DWPC 07-14-2015 04:11 PM

Are you perceiving turbo lag, or a 16 yr old engine with 115K miles on it?

wrinkledpants 07-14-2015 04:26 PM

Age shouldn't matter. I'd bet a properly running CTT with 200K miles on it will make close to factory HP. It's the neglected cars that have a steady decline in performance over the years.

Temperature and elevation will make a big impact on how fast your turbos spool up.

Paqueras 07-14-2015 04:43 PM

My TT is a 2006 with the E81 Power Package and the lag i got is minimun.

Check is your diverter valves are ok, if not replace them. The OEM ones are cheap.

bradbeck 07-14-2015 10:13 PM

Thank you all. I'll test drive it again using the manual mode.

Paqueras: since I don't own it, is it easy to look at the diverter valves? What would be the best method to view them?

If the next drive experience changes my thinking, I was planning to have a PPI, even though it is near mint.

The one item I forgot to mention is with regard to the front passenger seat. At some point, someone placed either a hot pot on the seat or spilled something that changed the leather on the bottom cushion and a small part of the back cushion. You can see where and the leather is stiff instead of the soft leather in the rest of the car.

I did run the VIN using the link on the other thread. Thank you for that.

The option list includes a pre-heater. I assume to warm up the interior before getting to the car or does it pre-heat the engine? It was an interesting option.

What performance upgrades should I look at to help with this lag? APR has a stage 1 for $2,500. Spendy...

knfeparty 07-14-2015 10:32 PM

The pre-heater burned gas to heat up the car's interior. I can't believe it's even legal in the US, but seems like a pretty awesome option if you live somewhere cold.

Check out my "TLC" thread to see some serious leather cleaning I did. I bet a couple leatherique treatments will fix up that stiff leather.

wrinkledpants 07-14-2015 10:39 PM


Originally Posted by bradbeck (Post 12432530)
Thank you all. I'll test drive it again using the manual mode.

Paqueras: since I don't own it, is it easy to look at the diverter valves? What would be the best method to view them?

If the next drive experience changes my thinking, I was planning to have a PPI, even though it is near mint.

The one item I forgot to mention is with regard to the front passenger seat. At some point, someone placed either a hot pot on the seat or spilled something that changed the leather on the bottom cushion and a small part of the back cushion. You can see where and the leather is stiff instead of the soft leather in the rest of the car.

I did run the VIN using the link on the other thread. Thank you for that.

The option list includes a pre-heater. I assume to warm up the interior before getting to the car or does it pre-heat the engine? It was an interesting option.

What performance upgrades should I look at to help with this lag? APR has a stage 1 for $2,500. Spendy...

You can't fix turbo lag with tuning. You can help the turbos spool faster with bigger downpipes and higher-flowing pre-cats, but that's about it. It's the nature of the beast with turbo cars.

Sniffer 07-14-2015 11:24 PM


Originally Posted by bradbeck (Post 12432530)
Thank you all. I'll test drive it again using the manual mode.

Paqueras: since I don't own it, is it easy to look at the diverter valves? What would be the best method to view them?

If the next drive experience changes my thinking, I was planning to have a PPI, even though it is near mint.

The one item I forgot to mention is with regard to the front passenger seat. At some point, someone placed either a hot pot on the seat or spilled something that changed the leather on the bottom cushion and a small part of the back cushion. You can see where and the leather is stiff instead of the soft leather in the rest of the car.

I did run the VIN using the link on the other thread. Thank you for that.

The option list includes a pre-heater. I assume to warm up the interior before getting to the car or does it pre-heat the engine? It was an interesting option.

What performance upgrades should I look at to help with this lag? APR has a stage 1 for $2,500. Spendy...

That is a sweet option and one I wish my CTT had

I`m even thinking of retrofitting a Webasto to help combat scored cylinders from cold starts.

touareg 07-15-2015 12:03 AM


Originally Posted by wrinkledpants (Post 12430561)
I drive like an old man, and the tranny has learned this behavior, which sucks. Sometimes, I'll come out of a slow sweeper, and it is still in 4th at 1200 RPM when I'm now trying to accelerate pretty fast. I have to remember to manually downshift it coming out of that corner.

Hah, I have the same problem. In the burbs, I don't touch anything, when in the city I hit the sport button so I can drive like a jerk in a sea of jerks and get the truck to react the way I expect it to.


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