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I was wondering if anyone has ever had to replace their throttle body or boost sensor on a cayenne turbo. Mine is a 2004 CTT with 60,000 miles with evom tune and typical upgrades. I have been having issues with hesitation and surging with acceleration and went through the typical steps (replaced all coils and plugs, clean MAF sensor, etc.) I am not getting any CEL's. I just recently cleaned the throttle body and noticed a dramatic improvement in the problem. I also did the throttle adaptation after cleaning. My issue is coming back again and I tried the throttle adaptation again which gives me some improvement. I did notice when cleaning the throttle body that its resting position was not perfectly at 90 degrees and it had a very slight angle to it. Could my throttle body need to be replaced or do they all have a very subtle angle at its resting position. My other question is if a bad boost sensor could cause these problems. Thanks.
Martin
mbagge01, did you ever figure this out? Did you ever order a new TB and did it help?
Sounds similar to my current situation, I have always questioned my TB cause if I hold it while reving to around 1000 rpm, it hunts up and down, up and down, not I am having surging issues, wierd acceleration, poor power at higher rpms.
I have no codes either, so dont want to just start throwing parts at it, although a TB isnt too expensive.
Ive cleaned it, but was also debating opening it up and cleaning the contacts on the electrical side in case.
I have a 2004 CTT that I've been fighting several codes/symptoms similar to the idling you've mentioned. I've replaced the throttle body and pedal position sensor (new pedal). I was able to clear throttle/pedal position codes, but I'm still left with an odd idle. Once warm it settles in at 1000 rpm, if I rev, it'll drop to 600 but then head back to 1000-1100. It doesn't stall on rev but comes close, especially if I put it in reverse. Hoping someone has a solution, I'm getting tired of chasing....
I'll reiterate what the last two posters wrote. These cars are 15-20 years old. There are certain items that must be replaced at this age or you will be chasing problems endlessly. I've written about this before. Valve cover gaskets are one of these. Others include the crankcase breather diaphragm, various coolant lines and vacuum lines, coolant reservoir and of course coil packs and general maintenance items (plugs, filters, etc.). Anything plastic under the hood is going to be brittle at this age. If you don't know the history of these items, then I would take care of them. At a minimum, visually inspect everything. This is not "throwing parts" at the problem, this is reestablishing a baseline for the engine and taking care of parts that, if not already failed, will likely fail soon. The car will almost certainly run better and will undoubtedly be more reliable.
BTW, off-brand or Chinese coilpacks are essentially guaranteed to give you problems right out of the gate. Beware of RockAuto and similar, or eBay (shudder).
Believe me, I'm well aware of most everything under the hood. I picked up my '04 CTT with 70K miles because original owner didn't want to deal with coolant tees. I also have a '06 CTTS that I keep sorted as well. While working on the coolant tees on the '04, I replaced most all vacuum hoses as they were brittle and broke a couple while removing/reinstalling manifold. I also replaced purge valve, valve cover gaskets, coil packs, plugs, brake booster, diaphragm, starter and thermostat just to name a few things . I've sorted out just about everything possible, but just been plagued by random throttle codes/issues, which led me to replace TB. After replacing TB it ran great for 5 months, then threw the pedal senor error and went to limp mode. I replaced the pedal sensor, did a throttle reset, and adaptation which resolved everything except for the idling issue.
I spent the morning trouble shooting, it appears the issue may be within my TB connection from the wiring harness. I disconnected, cleaned connections best I could, connected and did a throttle reset. Drove it 20 miles and so far it's holding idle at 600 rpm and sounds and runs smooth. Fingers crossed.....
Same here, i know my CTT and its issues inside and out, and i know age more than miles can degrade stuff.
i don't come here asking questions without some trouble shooting or checking the common problems.
aos is new, just did valve cover gaskets, ive replaced several pladtic hoses as they have failed, brake booster, purge, ones of the throttle body, 3 way aos valve breather lines, etc. Smoke tested, no leaks. Throttle body additions and trans adaptions multiple times, still have this odd miss on the throttle when reving and holding it around 1000-1200 rpm dropping to idle them back up every though my foot is steady It feel something similar when driving but under full throttle, which i can't demo via revving due to soft limiter.
Bbbb Bbbb, what exactly did you clean? I used electronics contact cleaner on the connector and throttle body side of the wiring, so male and female ends at the throttle body, anything else, maybe the pedal side connection?
i have been thinking of removing the black cover on the side of the throttle body to check and clean those contacts. Did you do those?
Last edited by Corvetteboy6988; 08-30-2023 at 02:26 PM.
I did the male and female ends as you described. My issue was the connector clip. One of the side rails that locks it in place is broken and I had to make sure the connection was tight.
Did you do both resets?
1) ignition on for 60 seconds (no start, just on), then off for 5 seconds, then on for 15 seconds.
2) adaption reset - ignition on, within 10 seconds depress gas pedal all the way to stop. Remove key while gas pedal is pressed. Release the pedal, insert key and start.
I also replaced my pedal (which includes pedal sensor). It may have been just the connection all along, but pedal sensor was not that expensive so now it's new. Will probably jinx it, but I haven't had the issue since my last post on 5/8.
Ok thanks for the clarification on the cleaning. Ill do so again, just to be sure the connectors are well cleaned.
I did the following on different occasions and on mutiple occasions:
1. throttle and kick down adaption via icarscan
2. the wait 60 seconds till you hear the throttle doing its thing, then off, then back on.
I dont believe I have done the other, version, but I do recall maybe reading about 996/997 guys doing this? Ill go try it today. This does sound like the icarscan one, as you press the pedal to the floor as well.
I ordered a new throttle body, not terribly expensive for the OE Bosch unit (sames as the OEM minus the Porsche packaging and branding). If it doesnt help, Im just gonna send it back. then Ill move on to the pedal sensor.
Installed the new bosch throttle body yesterday, same part as my original, but 1 revision number newer, 14 ipo 13.
no change to the wierd idle if you try and hold the revs around 1000 rpm, actually it occilates quicker now up and down, 1 sec frequency.
can someone try this, barely touch the pedal to increase the revs slightly. If i get above 1000-1200 it holds the revs fine.
But while driving it feels better. Some of the jerky behavior on and off throttle is gone, and it pulls fine now full throttle 2700 - 4000 rom.
Im gonna take the old one apart and see if the contacts are dirty behind the blsck cover. My old throttle body was and clean, as i just cleaned it when doing the water pump in march, so i know that wasn't the issue.
for The relatively low cost i am satisfied with the results. Its not like I'm holding revs at 1000rom....ever. I only discovered this the 1st time I used CRC intake and turbo cleaner and you have to hold the throttle while spraying
Did you ever replace the electric/ wiring connector which is going to the throttle body? Same with the wiring itself. Symptoms you describe I had . It was the wiring and the black plastic connectio
n
No i just cleaned the connector.
ive replaced connectors like these before going to the air strut.
how did you replace yours, splice in a,new one, just the connector itself?
You mentioned wiring, where was the bad spot, how far back from the connector?
You could even try to wiggle the wires going into the black plastic connector. In my case , touching the wire and move it a bit immediately caused stumbling in idle and sometimes the engine even died. You have to make sure , al single wire going into the plastic connector is sitting proper. Solution: buy a new connector incl. the wires or strap the old wires from the connector and and renew. I am German, I really don’t know how is the English word for this process. Some electric specialist could answer this question. I understand you are very handy, you can do it yourself.