Vario cam valve lift solenoid?
 

The C4S saga continues... this time multiple engine warnings regarding the PASM, Engine control etc.. car sputtered and coughed at idle and was running rough at low engine rpm's. Dealer called and told me it was the vario cam solenoid - however they want to keep the car for a few more days to 'make sure". Have not seen any 991 threads with this issue.

Can you ask the dealer what were the exact codes they've found? I wonder if they'll tell you...
I'm just curious...

I want all the details you can throw at me about this... I have a stumbling issue at lower RPM that I am convinced is related to the variable cam.

Sign me up as well. Feels like the car is missing. Only really notice it in eco mode...sport mode not so much. :confused:

2013 C4S PDK - Car has not triggered a check engine light.

Me too please...

+1 please!

Could this be the answer to the 2500-3000 RPM stumbling issue?

This is why we want details! :-)

I'm so desperate for possible solutions that any time there is a thread remotely related to rough running I'm all over that!

This is truly pathetic.
A desperate bunch of owners (yours truly included) searching for an answer to an issue that Porsche simply will not acknowledge.

@WJkelly3
Any news on your car?

Thanks

No details on the codes and I haven't driven the car since it was returned. Will update after some driving this weekend - the rough idling always occurred after some aggressive driving followed by some mundane city stop and go. More to follow...

Thanks for the update. Those of us desperately seeking an answer to the 2500 rpm stumble would love to know if this is in any way related to a VarioCam actuator or solenoid failure. Unfortunately, I don't think any of us have had issues with engine warnings or rough idling. (My kingdom for a fault code). :crying:

Does the 2500 RPM stumble affect Manual Trans and/or 3.4L engines also?

I dont have a stumble but did notice that the PDK engages the clutch at 2500 RPM, which does bog the engine a bit, if throttle is too light.

Yes. Both manual and PDK, as well as both 3.4 and 3.8.

I see that there are several threads on this topic. Is there a more appropriate thread for this?

My experiences (i.e. twice) with this issue have been dramatic. The words "stumble" and "hesitation" are completely inaccurate to describe my events. Both times this part has failed, the car was barely drivable, and would not muster 40 MPH (probably not even 30, but I didn’t try anything faster than 25 MPH due to the fact the car was clearly in physical distress. Now I’ve had gentler, milder, fleeting events happen before that I now recognize as similar to what others are describing. I’ll talk about those later. First, let me tell you about my experience when that bit gives up the ghost for good.

First event: Gently driving about 30 MPH through a secondary street, I approach a red light. As I stop, the car stumbles, misfires, almost dies, and begins to run like a V8 whose cam timing is off the mark.

[Pop… shutter, shutter, shake… cough, pop…shutter, shutter, shake]

The dash lights up with (IIRC) PSAM disabled, Engine Fault, and a third warning I do not recall. Fortunately, I was 4 blocks from home. The car was dramatically under powered, and adding throttle felt like an act of violence against the engine. I limped home, and called the dealership. I was in the final months of the standard warranty, and the dealership sent a roll back. The original fix was to the VarioCam solenoid, and my service advisor told me the thing somehow came unbolted. The dealership experience was fine, and life went on. That was about a year ago.

Second event: A few weeks ago, I am on the interstate for about an hour, glued to the speed limit (Memorial Day weekend- every cop in the state is on traffic duty). After about an hour of driving 70 MPH, I take my exit ramp. As I reach the stop at the end of the ramp, I start to feel a shaking. My first through is that I was in manual mode with the PDK, and failed to downshift from top gear. That’s the feeling the car had- lugging the engine with a manual transmission. As I stopped I hit the downshift control on the steering wheel, but the problem remained. By the time my wheels were still, the warning notifications begin flashing. It was clear the same thing had happened. The valve lift (or maybe it’s correctly called the VarioCam Lift Valve Solenoid) was inoperable, and the cam was in the wrong position. See event one for a pantomime (text-omime?) of my experience.

I went back to my dealer with the expectation that since this was repaired by them less than a year ago, either there is a widespread defect with this part, or they didn’t properly fix the item when it was repaired under warranty. I made my case respectfully but firmly to the service advisor. Though it took several days, he was successful at negotiating with Porsche to cover part of the cost to replace this part a second time. It may have helped that I take business to that dealership that I could have done cheaper at an independent shop, and it definitely helped that the service records showed the part failed less than a year prior.

I’ll come back later with some information on the intermittent events I now recognize were short term malfunctions of this part, which preceded the outright failures I’ve experienced. For now, I’m back behind the wheel of a car that is almost sublime when driven gently, or a snarling beast when I find a few hundred yards of open tarmac. But I do have a suspicion that bit is a weak spot of these engines.


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