2011 Cayenne S check engine light keeps coming back

[Dopeyskydiver]

Hi all,

 

Can't seem to get rid of fault code P1376. It can be reset, but comes back within a few days. (Car seems to run fine)

 

The local independent garage hooked up their PIWIS and verified the P1376 code - said it was something to do with cylinder #8?

 

Has anyone else experienced this - and if so, what was the fix? Any tips/advice is appreciated!

[Loren]

Likely the valve lift solenoid if you have checked the wiring.

[Dopeyskydiver]

Thank you Loren! I will check the wiring first.

Just out of curiosity, I believe the valve lift solenoids can not be individually adjusted, but per bank (side). Is this correct?

 

Would it then make sense to change all solenoids, or just focus on #8? (My Spidey-senses are tingling and saying to change them all...)

[Loren]

As I have said before "if ain't broke...".

As well, you might want to check the price and labor of replacing just the troublesome one.

[Dave Math]

Circling back to see if this was resolved before I start a new thread. Hope that's not too old of a thread to bring back from the dead. With no answer I'm continuing the discussion.

 

I've got a 2011 Cayenne Turbo, with P1376 on cylinder 8, small. Plugs and coil packs are good, no major scoring visible on the cylinders via boroscope. Compression is 240-270 with the #8 cylinder at 265. Car runs well, slight cold rough idle that passes. 166k miles. Oil is new. It was generally clean under the valve covers as the car was serviced to spec.

 

 

Car has had the recalls done for the variocam bolts. The crankcase ventilation system and oil cap probably was replaced once in its life, but is showing its dirt today.

 

I have a dropbox with values from the cams via the iCarsoft Por reader. I put some photos in there of the #8 cam and bearing, I see a little bit of wear, but no scoring. I have not removed camps to inspect the hydraulic valve to inspect if its got wear.

 

This link should work without dropbox login, at the time this was posted: https://www.dropbox.com/scl/fo/tcv1m5xt8sg92djz3pvqm/AJqYRXuGM80XYlI0zks1KZ4?rlkey=1ut8p119503jf6tcwnji8cqd6&st=tryart2w&dl=0

 

Further questions for troubleshooting:

Does the valve cover ventilation system and oil cap pressurize the oil system for the lifters?

What does the P1376 small vs large mean?

I can clear the code and then see it again stored and pending, it's coming back.

Since I am only getting one cylinder error, that is closer to the variable solenoid at the rear of the engine, this tells me that the solenoid is working, because other cylinders aren't seeing the error. 

If the cam was failing due to metal fatigue, or bearings, I should see more than one cylinder erroring out.

The tabs on the camshaft for the position sensor are intact, I've read they get snapped off during valve cover reinstallation. This sensor should work or not, I assume there is no "half work" on hall effect sensors.

 

That's enough for now!

 

[JE 17]

I’ve fought this for a few months. Initially got the variable timing unit replaced by mistake. Spoke with head tech at a dealership about while there for another issue. He was kind enough to explain how to change the lift solenoid without a lot of difficulty. He suggested removing the panel behind the engine for better access. Also, you’ll need an o ring for the vacuum pump as that must be removed. 
Since it seems to only appear from cold, disappearing once warmed, I’m going to put this off a while. Building an engine for one of the Boxsters takes a lot of time.

Edited Saturday at 02:47 PM by JE 17
Auto-incorrect

[Dave Math]

Thanks JE. So you think it's the lift solenoid for your engine? What codes are you seeing on yours? Most people with the solenoid issue have errors codes on many cylinders, and I only have #8 issues, so I'm not sure if it's just a lifter or what...

[JE 17]

I'll see if I can look it up, but that sounds correct but I only had one bank, I think 2. 

Yes, I'm certain it's the lift solenoid.