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2002 Porsche Boxster S, 6 speed, having a strange problem where the heat only comes out if I put it on hi, then it gets hot as all hell, have to turn the fan down. If I click the down button the first temperature it sets it too is 85. Then its cold. If I lower the temp it gets colder and colder, AC works gets icy cold putting the temp the other way.
But no warm air, only hot air, and only when set to HI. Any thoughts on what to look at?
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!
2007 Carerra S
Firsly, my apologies for the long account of events, but my car has been in/out of dealer about 6x in 2 months. They can't figure this out.. so i'm hoping someone out there can shed some light on this.. thank you!
I have had an ongoing and increasing problem(s) for about last 6 months. Not sure if these issues are related or coincidental, but here goes....
Started out with the car dieing out upon its first startup every morning. It would always start up perfectly the 2nd attempt and then a little rough but then even out and be great after that. Dealership said to run a can a seafoam through the gas every other fill up. This would slight help reduce the problem to intermittant but not complete improvement.
Then I noticed the idle becoming a little bit rough at times and gas mileage reducing from about 16 mpg to about 11mpg without any change in driving habits. I also would occasional notice it difficult to smoothly start moving off from a stop because of a slight engine hesitation and found myself giving it more gas that usual to start off the 'line'. (Never felt like a clutch slipping issue). Also cruising between about 3000-4000 rpm I could feel a slight infrequent 'hesitation' in the acceleration.
Then I started to develop (what dealer calls) a 'hunting' idle when stopped with engine running. I also noticed a drop oil pressue to near minimal to what looked like zero at times on the gauge. Then one day the a/c starting blowing warm air along with significant drop in Oil pressure. Dealer replaced the Oil pump.
The 'hunting' idle continued whereas I would be sitting still with engine running and see the rpm fluctuate from about 750rpm and rise up to 1200 and drop to as low as 300. The odd part is this would happen at EXACTLY 20 second intervals. If i gave it some gas.. it would stop for a few moments then start again. (NOTE.. I NEVER HAD ANY CODES or ENGINE LIGHTS).
Dealership replaced the Mass Air Flow sensor ( MAF) .. of which did not help and 2 days later not only did it still hunt.. but actually died out sometimes while idling. I took it back in and dealership said it was the Crankshaft sensor causing the hunting and carbon buildup causing the initial startup problem. They did a engine decarbination and replaced the Crankshaft Sensor.
I received the car back again and STILL had the hunting problem along with the 'hesitation' feel with low speed cruising.
Seemed to be worse when engine was hot. Then one day during the crazy hunting / hesitation issue i pulled into my garage and opened the drivers door and smelled an intense FUEL smell which was coming from the right front fender area.
Took it back to the dealer who swears that there is nothing wrong with the fuel system or vapor canister, etc. (note.. the fuel smell only happened 2 or 3 times and dealer could not reproduce it). HOWEVER, this time they noticed when they gently rested their foot on the gas pedal the RPM when into a crazy constant hunting mode from 750rpm (up to about 2000 down to about 400). Again a ECU code still has NEVER came up.
Dealer disassembled the Throttle body and cleaned it up, then reistalled. Still had the hunting problem and hard 1st start issue. So they ordered and installed a NEW throttle body. Still no change int the problem. So he put the new Throttle body back on and (oddly enough) discovered it was nearly impossible to remove the oil cap while the engine was running. So he determined it was the Oil Seperator that was bad. NOTE: It never had smoke emmiting from tailpipe or any CODE thrown.
So.. they replaced the Oil Seperator which appeared to stop the hunting problem, rough idle and hard start problem. HOWEVER, THEY NEVER FOUND THE REASON FOR THE FUEL SMELL?
I picked up the car 2 days ago.. This is the current status of things...
The hard initial start is much better.. so far has started up on first attempts... and Resting idle is pinned at about 750rpm and doesn't move.
However, I still feel a slight intermittant hesitation when slowly accelerating or trying to maintain about 3-4k rpm.
AND... at idle.. if i rest my foot gently on the gas pedal.. (for example.. trying hold about 1,000rpm, I still get hunting significant hunting oscillating the rpm from 750 up to about 1200 and down to about 500)
The service manage said this is normal because the car thinks i'm moving and i'm not?? huh?? If i try doing this when engine is cold or warm (just after intial warmup) it doesn't do it... but will do it badly when hot. NOTE this is the Arizona heat! Service manager feels this is normal and stated it was hunting much higher before with light pedal touch, but says this is normal.
Can you PLEASE let me know your thoughts on this? I do not think a light touch of the gas pedal should cause a crazy oscillation of the RPM's. Also the car still feels like its hesitating during slow, smooth acceleration.
Like its trying to take a breath while its increasing speed?
Does it sound like a fuel issue? They stated fuel pressure was good, but they still do not know the cause of the fuel vapor leak/smell from before? The gas mileage is still at around 12 mpg (with standard driving)
The one thing the service manager also cant understand is why the ECU still hasn't thrown any codes during any of this?
Could the ECU be bad?
Can a worn clutch cause any of these symptoms? (its never during shifting)
Why the gas smell/bad gas mileage, etc?
Please... any suggestion would be greatly appreciated!! THANK YOU!!!
Hi everyone. I have a 1998 996 C2 manual RHD. About six months ago the heater/climate control fan started messing about. Mostly it would work, but now and again it refused. This became: usually worked at first start-up but thereafter usually refused, but might spark up at some point during a journey. (it seemed to me that opening a window[because I was fogging up] kick started the fan, but that may be coincidence)
The little fan under the passenger air vent was a little noisy and sometimes the heater fan would click a bit like a bicycle wheel with a playing card pegged to it.
I changed the ignition switch (read about intermittent electrical maladies being linked to it). No difference. I bought as new (S/H) heater fan and when I took mine out found that the connectors weren't compatible so I had a good look around and put mine back in (I read that when fans stop they stop, they don't work sometimes and others not). I then replaced the little fan under the passenger air vent. Again no difference.
Rather than be intermittent the heater fan has stopped all together now. So I have just replaced the heater/climate control panel unit (klimabetaetigung) with one that has exactly the same numbers as mine. It seems to work fine - I can hear lots of things happening when I change vents, switch aircon on and off etc. But still the heater fan won't do what it should.
I'm at a loss to think of what else I can replace - I suppose the heater fan could have finally given up the ghost after a slow painful death, so I can replace that.
The only other thing that seems wierd is that when I changed the little fan under the passenger air vent the climate control (when it worked) seemed to think the car was around 5 degrees hotter than it really was - put it on max and warm air comes out, but turn it down below 27 degrees (when you know the cab's no hotter than 21) and cool air comes out. I have no trouble with coolant or air con, all checked and serviced by Porsche.