Well I got the dreaded P0021 error for bank 2. This would come once a year and after reset would not return for another year. But last week it came, and resetting it would bring it up again in a couple of minutes.
So I did my research. Many people suggested replacing the hydrolic actuator on bank 2. A 20 to 30 minute job... Ya right....
The first hurdle was finding it. No one ever mentioned you need to remove the airbox and the intake.
Once this was done, there was a nice plastic wiring harness over it which I couldn't figure out how to move. So I bought a number of tools to get that ==@))=@%ing bolt out. The only one that worked was a wobble extension. However during the process I dropped the socket head at least 40 times and at one point it took 45 minutes to get out using a magnet and a flexible video cam.
Once out all of a sudden the plastic wiring harness moved up. All I had to do was pull up a bit.
So now, I put it all back and then found I left off the little rubber protector off the top. So the air box came off again.
The mention of truth... Started up the car, a few misfires and then a P0018. Shut the car down. Cleared the error and now have driver 20 minutes with no errors...
So the 20 to 30 minute time took me with two trips to the tool shop took 10 hours...
I hope all is OK now.
Yikes!

 

Well the P0021 came back when I started up this morning.
Cleared it drove 1 hour and its still off.
Looks like I might need a camshaft.
I hear that there is a revision to the original cam and that it addresses the spun bushing.
Any truth to this?
Thanks

 

Sorry to hear about your troubles. Unfortunately there's no new camshaft that I know of but you can have them pinned. What oil are you using? Have you changed it recently and is it related to your issue?

 

Bi
I'm using 0w40 Mobile.
The oil was changed about 200 miles ago.
It seems the cell only pops up at idle.
I just went for a 20 mile drive and nothing happened.
So where does one get a camshaft pinned? Should both of them be done?
Thanks, Sam

 

It's a major job. Like an engine job. If you are not down on power or feel anything crazy (which I doubt) try to ride it out a bit. I am working through this issue now on a car with pinned cams. But we ran break-in oil and then 50wt. Gonna see how it goes with an oil change. We can also log it. Are you tuned?

 

No, the power is just fine. As far as I know I am not tuned. Bought the car used at Porsche with 18k miles and 2 year CPO which expired 2 years ago.
So you have a car with pinned cams and you still have the errors?
Tom

 

Ok I got this from Rentech forums...
Might be good to verify

Camshaft. - this is interesting. Supposedly the new camshaft is a different part number than the original. It's been modified by Porsche so the "spun" issue is no more. Also no pinning is required. This is what the 20+ year tech told me. Was surprising to hear. Part number is 997-105-020-74 and I think it replaces 997-105-020-73. This is my best guess as I looked up the part. Just going by what they told me. So I only have to be concerned with the other cam in bank 1 for all eternity. The Cam itself was completely blocked and wasn't letting oil through.

 

I had my camshaft replaced just before my cpo warranty ran out. Around that time the Porsche mechanic was learning how to pin cams with instructions and parts from Protomotive. You could ask your local P dealer if they are familiar with this procedure. If you are going to do it I would do both sides. And consider a few upgrades "while you are there", lol.

 

So do you use new cams or just pin the old ones?

 

Always pin. And +1 remember/heed the old while you're in there thing it creeps up on you fast! But you can do some other things like rods and head studs giving the work more value.

 

Like Sambo mentioned earlier, I would try to drive it a bit. Me, and several others on the forums have had the occasional camshaft error. I changed the valves on the side, and solenoid/actuators, and it came back (very seldom). What I believe must happen sometimes, is it either gets a spec clogging it, or turns slightly....I have just gone out and driven the hell out of it and it goes away for maybe a year or more in my case....

Just offer that up as a data point.

Good luck!
DC

 

Hi, DC,
Well you guys may be right. I went out today did about 50kM and no cell. I did have it intermittently, like once a year or even less, but when it came back this time, it wouldn't stop even after changing the sensor. However, it now has.
So I changed the sensor, but what are the solenoids you mention?

Also, this all seems a little fishy to me. If the bushing or whatever it is, slips and blocks the hole, why would it go away? The camshaft only turns in one direction so the hole would eventually get totally closed.
You would think that it would always give the error from that point.

 

Yeah they get dirty too. Sometimes the code seams to come on and you will notice the oil was cold. What I can't figure out is what exactly makes them fatigue or it's just some soot slowing them down.

 

Well one thing I have noticed, the P0021 only seems to come on when the engine is cold or I am idling at a red light. Never when driving. So this would indicate a low pressure oil supply. Are these cams hollow? Does the oil flow through them and out the hole?
Has anyone actually seen the hole blocked or is the cam itself just not delivering the oil? I've never seen a picture of the sleeve in an unblock and then blocked image.

 

Great to hear.....If it comes back, drive it hard just for a few minutes. When I have gotten it, it was usually cold as Sam indicates.

I go out and punch it to the floor a few times, brake, and punch it again...hard acceleration then let off the gas quick....Whatever it jostles around it there did the trick...

Here are the parts I was referring to.




DC