purrybonker

I've had repeated intermittent CELs with my '06 C2S over the past year.

Codes P0018, P0021, P0300, P0304, P0305, P306 reported 18 months ago.

Dealer did a bunch of things including checking the cam timing, coils, plugs found no faults, replaced a cam actuator solenoid, cleared the codes and sent me on my way.

Codes P0018, P0021, P0300, P0302, P0303, P0305, P0306 reported last month.

Car was also in for RMS under CPO, so the dealer noticed a clicking sound in the flywheel, suspected culpability and replaced it. Also replaced bank 2 camshaft position hall sensor. Cleared codes and sent me on my way.

Codes P0018, P0021, P0300, P0302, P0303, P0305, P0306 reported last week.

Dealer reprograms DME, sent me on my way.

Codes P0018, P0021, P0300, P0302, P0303, P0305, P0306 observed yesterday.

Dealer scratches head. Asks to use a lifeline.

utkinpol

http://www.obd-codes.com/trouble_codes/

camshaft position, misfires... what year is your car? Some 2005 cars seemed to have issues with faulty DME what was causing unexplained misfires.
sorry just saw your car is 2006. no idea.

Macster

P0018 - Crankshaft position with respect to bank 2 intake camshaft.

P0021 - Position of camshaft in relation to crankshaft, Bank 2 below limit.

The P030X codes are misfires with the X denoting the cylinder.

Both P00XX error codes point to bank 2.

Let's see.... Well, I note the VarioCam solenoid was replaced but not the actuator. Recently my 02 Boxter had the solenoid go out and it was replaced but for some reason the actuator was not, even though I was told later it was SOP to replace both items. I was not given the choice but had I been asked I would have relied upon the tech's advice and agreed to replace the actuator too.

As a result the car developed the same symptoms/error code (not the ones your car developed though) and the actuator was replaced and all I had to pay was the additional labor required to go beyond the solenoid and the parts specific to the actuator replacement.

So, I would suspect that the actuator is bad. (What I think happens is the solenoid goes goofy and this wears out the actuator. Then the solenoid finally goes bad enough that it fails (only in my car's case to resume proper functioning for a while) and the solenoid is replaced. Only after the solenoid is replaced can the actuator then make its sorry state known.

But are my suspicions enough to tear into the engine again and replace the actuator? No.

The crankshaft position sensor can be a suspect along with the camshaft position sensors. The sensors, their connections. Wait I see where some sensors have been replaced.

You're going to need more. It would be nice to know what tests the dealer has done to see if it has exhausted the full string of diagnostics tests. IIRC each cylinder bank's cam timing and variable lift can be activated or disabled and the behavior of the O2 sensors can be observed to determine if the cam and valves and lifters/etc are behaving.

Now I note both cylinder banks are experiencing misfires... Probably a long shot but worth the cost of a new filter and some oil: Has the oil filter housing been removed and checked for signs of a camshaft chain tensioner/rail (the composite plastic) in the oil or the filter?

Absent anything else that I've covered above I'm going with a common failure and that sure takes in the engine controller (DME).

But should you replace the DME based on my suspicions? No.

Sincerely,

Macster.

purrybonker

The tech is in agreement with you on this - it is being replaced.

I think suspicions about the crankshaft position sensors being at fault was the reasoning behind replacing the flywheel - that and the observed "clicking sound"

Thanks for the remarks - I guess we'll see how it shakes out with the replacement of the actuator. I'll post an update later.

ExtremeJoJo

My 07 Cayman 2.7 has those exact same codes, I know this is an old post but did you ever get a definitive answer on the cause of those codes?