CAVU

What ever your coil pack swap strategy is, be sure and include easy access to the suspect coilpack. As you are aware, some coil packs are easier to access than others.

DemonBG

Very good point, Thanks CAVU.

DemonBG

Update:
New plugs & swapped my left and right bank of coils and the problem persists largely unchanged... Initially my misfire on cylinder 3 got worse but after a short drive that seemed to clear up again...

So far i have:
Added engine oil flush
Changed oil and filter twice
Changed spark plugs
Swapped coil packs
Charged battery
Added fuel system cleaner (Techron)
Sprayed seafoam though top end

Currently my rough idle is much, much better than it used to be - but the rough idle is still there and continue to get error codes:

• P1361 - Valve Lift Control - Cylinder 2
• P1362 - Valve Lift Control - Cylinder 4
• P1363 - Valve Lift Control - Cylinder 3
• P1372 - Valve Lift control - Bank 1

So now im thinking the valve solenoid needs to be replaced in the right (passenger) side. I found this guide by @Doug_B_928 for a 2008 CS:

https://rennlist.com/forums/cayenne-...placement.html

How similar do we believe these engines to be? Would this guide "Largely" be the same for the 958 CS or would i need to remove my valve covers?

Thanks for the help all,
Demon

Side note:
While doing my maintenance i discovered some wetness in my passenger side footwell.. Traced it to blocked drains in my sunroof which is now fixed and i ended up checking over the wiring harness to make sure nothing was damaged. Didnt find any corrosion or broken wiring so i got away with that one. FWIW there is an oil control module under the passenger seat as well so i took this apart and checked to make sure no water got inside. Again, no sign of liquid damage so i cleaned it up with electrical contact cleaner and reassembled.

deilenberger

Demon - have you looked in your AllDataDIY subscription? That should tell you what's required.

DemonBG

1am quick update (Detailed to follow).

She's Fixed! turns out it was the valve lift solenoid that had failed and it is quite the task to replace it - But i did find a much easier way to do it without having to take off the intake manifold or valve covers..


details to follow. for now... i need sleep!

CAVU

Me thinks you approached it from underneath the car?

DemonBG

That depends.. Do you count the wheel liner as "Underneath"?

Turns out if you remove the wheel (Fender) liner the passenger side (Bank 1) valve lift solenoid is very accessible... Or at least, it would be if it didn't clash with the vacuum pump.

Removing the 2x E-torx botls for the valve solenoid was easy and took 10 minutes.
Removing the 2x lower E-Torx bolts for the vacuum pumps was slightly trickier and took about 15 minutes. But not bad.
Removing the upper 1x E-Torx bolt for the vacuum pump was an absolute B@stard due to the proximity to the firewall and all the other pipes that pass nearby it so it took about an hour. My end solution was to use a 5/16th fine tooth ratcheting wrench to loosen it and then remove the screw by hand.

Overall it took about 5 hours to remove both the solenoid and vacuum pump, rebuild the vacuum pump (My vacuum pump had some scoring on the inside which i took some time to polish out) and put everything back together.

If i was to do it again it would probably take 1.5 - 2.5 hours start to finish as the hardest part was finding a tool to remove the bolt at the top of the vacuum pump.

I will create a write up once i get a bit more time in my day for anyone who needs to do this in the future.

All the best,
Demon

Krisek

Thank you!
have exact same codes... Where did you source the sensor from ?
Thx

DemonBG

hi Krisek.

I got the parts directly from the dealer. Was about $230 but you can get them from FCP Euro or a few places online a little cheaper... I was just in a rush.

good luck!

AudieO

Similar to my experience with 2012 CS 127-kmiles It was not driven for almost 4 weeks. Could the VVT dried up of oil and with the summer heat killed the sensor? The Porsche tech said the VVT sensor looks clean.

Thanks,
Audie

DemonBG

so they removed the VVT solenoid and tested it? If you had a VVT solenoid go bad then you’ll likely have engine codes and a CEL. What are your symptoms? At fault codes?

AudieO

My symptoms and codes are the same as DemonBG.

They did not test the solenoid. I think the solenoid has sensitive part like the MAF sensor.

DemonBG

if you have the same list of codes then the chances are the same part is failed. Also I dont think they have verified the solenoid us working or not. If you can’t replace it yourself, have another competent shop inspect it.

Wrecked Em

Thanks @DemonBG . This thread made it very simple to diagnose and repair this problem on my 2011 Turbo.

wyowolf

can you point out where? thank you

sorry I meant to pic above my V pump is leaking just trying to understand what exactly is where