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If I run the car at less than 1/4 tank full it's very smooth great acceleration and responsiveness. With engine running I went and filled up with 99 octane as usual and straightaway the engine stutter comes back!!!!!!!! Fyi it is NOT fuel quality.
I've started a new thread for this but it's an old problem mentioned in previous posts and unresolved.
Basically the ctt 06 with 114,000km has been hesitating and stuttering for a while when accelerating particularly under boost in lower gears through the rev range of 2k 3k 4k ish rpm, it also will vibrate and stutter revving the same rpm in neutral/park when stationary. (which is very weird).
So after a lot of finding issues which helped the car overall none of them sorted this stutter out.
New oem Coils, plugs, n75 valve, air filters, purge valve, and Dv's,
Fixed a lot of vac and pcv pipes which leaked
Smoke tested intake no leaks boost is +0.8
Head Gaskets done a few 1,000 km all new parts gasket Seals etc. (problem was present before and after head Gasket work).
I had a suspicion that the lower fuel level was playing a part in this but I can't work out why a fuller tank would cause running issues?
2007 Carerra S 114,000 miles
I have had a roller coaster ride of dealership attempts to find and repair a hunting idle, hesitation at low-mid RPM range and now a interrmittant intense fuel smell emmitted from right front fender area. If you refer to my previous Tech question you will see multiple parts have been replace trying to find this problem. Throttle body, MAF sensor, Crankshaft sensor, Oil seperator and now the car is back in again for all the same problems. They now have done a fuel system 'smoke' test and did not find any leaks. The mechanic now thinks the Charcoal Fuel Canister feels too 'heavy'? and thinks it might be over saturated with fuel and not purging properly? He thinks this might be causing an OVERLY rich gas mixture 'possibly' contributing to the idle, running and performance issues AND at its extreme moments of further gas fumes induced into the canister it is then purging out to the atmosphere.
Does this all make sense? I guess the fuel smell from this over saturated canister is possible.... but what about the performance, idle hunting, hesitation... etc issues? I should also note that the problems are usually intensified more when the engine is hot. The dealer has had the car on/off about more than I this past month. Any help is GREATLY appreciated!
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!
By Bruce in Philly
9A1 105 308 03 VVS (02 superseded by 03 variable valve system actuator)
Anyone replace one?
What are the symptoms?
How do you identify which one may be lazy?
How many per bank? The PET digram denotes (1) so I assume that is one per side no?
These appear very easy to replace as the sit next to the spark plugs. I will be doing my plugs in a few months, early spring so I am thinking of just swapping these out.
The reason is that pesky hesitation I get under moderate load at around 2800 RPM. The dealer, as others on various boards, think it is the variocam transition. This looks like about a $150 dollar each part. I am willing to throw $300 at this issue.
I do have the Durametric Pro.... but no clue as to what to look for regarding these actuators.
Bruce in Philly
2009 C2S Coupe
I have a 2004 Porsche 996 C4S with Tiptronic and I live in the UAE where the summer temperatures are +40C for 4 to 5 months.
When I start the car from 'cold' bearing in mind the car bnever really cools down here even though the car is always parked in a basement car park, after I have engaged drive and started to move forwards, the car sometimes feels like it might stall and has a momentary 'flat spot', after a few minutes the car's fine......
I've already changed the MAF, and no difference, could it be spark plugs or ignition coils or a combination of both?
Any help would be greatly appreciated