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My 2004 CS seems to be a little weak to get up & go since I got it last summer, but still much more power than the car it replaced. I wrote it off thinking, "it's not a turbo, so what do you expect?"


I did the plugs and air filters in the fall, and replaced the valve cover gasket on the driver side where it leaked the most. Still no major differences, not that I expected any.


Went out to buy some throttle body cleaner the other day, and on my way to the store I got a phone call which prompted me to turn off the climate control (click the fan speed down to 0, temperature display shows 'OFF'). On my drive home the Cayenne drove *totally* differently. Really ballsy on the pickup, tons of pull. 


A few days later, I realized the car was especially chilly / foggy, so I turned the climate control back on. Sure enough, she was sluggish again to get going!


Anyone see this kind of thing before, and know what might be causing it? As far as I know, most cars "back off" on A/C and heat when the driver calls for acceleration, but that's definitely not happening here. Also, with the colder weather I'm not sure whether the Cayenne is engaging the A/C in addition to the heat.


Any insight would be appreciated!

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  • 1 year later...
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Did you ever figure out the issue? I have a 2006 CS with only 62k miles and it does the exact same thing as you describe. I can't figure it out.  I have replaced with new parts the following: all the coil packs and spark plugs, changed the intake manifold gasket, changed both MAFs, air filters and AC Compressor. It still does the hesitation when driving with the climate control on. 


I bought a new throttle body gasket and throttle body cleaner. I'm going to try that tomorrow and see if it improves. I am not very confident it will work, but I will report back my results after I finish cleaning the throttle body.


In the meantime, if anyone knows what could possibly be the cause of this issue please chime in and let us know. 

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this is "normal" for 03/04 units. its a mixture of many things none of which are affordable for fix due to $


05 transmission improves

on the basis that you also have the matching set of tx modules


e-gas, is good and bad, a case of to much automation given that most poodle the car and do not drive it like you stole it. it sets profile, try driving crazy for 30 minutes and note the following change


try turning PSM Off and note the starting gear, if its now 1 you ok, if it remains at 2 you tx control unit is in need of replacing


EESCO1your smells of e-gas, post 05 the tx was better, good luck




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Interestingly I have the opposite issue. Mine is a 2004 CTT, and to my surprise it was running a bit sluggish, but when I opened it up with the a/c on, it had more kick to it. I think perhaps the ignition timing is being changed to compensate for the increased load on the engine by the a/c - we know from the factory these vehicles are vastly under tuned, so there is head room to push it to compensate. To test this I am going to log my ignition timing under the two conditions. I bet there is a difference.


But before spending a lot on sensors and gaskets, I’d try re-training the throttle and resetting the fuel trim and adaptations, if you have a cable. Although a clean throttle never hurts.


Added Note: I just tried driving it with the HVAC completely off, and it is stronger with mine too! Mudman, you say this is "normal" for the 2004's but costs too much to fix - do you know what the cause of this is? Thanks.


Edited by Zakowsky
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