Codes P300 p301 p302 p303 rough idle.

This is a 02 911 Carrera2 3.6L Was at AX event today. Drove to the event 30miles with no issues. Parked the car for 20-30min. Started the car. It was idling rough and then CEL started blinking and threw the above 4 codes. I'll also add that in the last 3 days during cold starts, the idle was slightly rough for 10 seconds but then would quickly go to normal. No CEL. I've reset the CEL. Started the car. Good idle. Drove for 2-3 miles with no issues. Then a full day of AX and a drive back home. The engine ran smoothly and no codes. This is actually the 2nd time I see these codes. The first time was when I was doing alignment. Tech brought the car to me and CEL was on. Drove it for 5 miles. Shut down the car. Started again and the CEL went away. On its own. 79k miles. The coils have a 2022 manufacturing date on them, puled a few plugs and they looked good a month ago when I bought the car. Gas was fresh. Oil (Mobil-1 5w-50) and a new deep oil pan were installed just before the issue started, though I don't believe this has anything to do with it. Any ideas? Thank you

I assume this is a 3.6 996.2 2002 2003 2004. The usual suspect is a variocam sticking or a vario lift lifter sticking... What brand/weight oil are you using and how long has it been since changed?...I have seen dirty oil cause these misfire codes on this particular engine...( but you forgot the give the year model)

The last oil change was less than a week ago. Mobil-1 5w-50 full synthetic This is a 2002 Carrera 2 3.6L I was also planning to put in some ceratec liqui moly as a preventative measure from bore scoring And in the future planning to switch to Driven DT40 which supposed to have the molly in it

Quotes source post: 19051208

What is the suggested course of actions here? Is there anything I can do without pulling the engine?

Quotes source post: 19051208

The car was parked for the winter and will be back playing with it this season. This is a 2002 C2 convertible I thought too the thicker oil that I put in could be the cause as the problem surfaced right after the oil change As I pull the car from storage, I will drain the oil and put in DT40 this time and I also was planning to put 2 bottles of Motul/Liqui Molly Hydraulic Lifter Additive. I know any sort of additives are not the best thing, but the actual question is: Do you believe it is a good idea to put in the Hydraulic additive one time to clean the passages or perhaps start doing it with every oil change now? Also planning to pull injectors and may be see a manufacturing date if it is on it and replace injectors preemptively if original to avoid potential bore scoring in the future. So far oil analysis is clean of metals, no fuel in the oil and the spark plugs look clean. Thanks for your input

Just to document the solution. I finally diagnosed and repaired the issue. The problem was with a driver side valve lift solenoid that was leaking oil was stuck open. Replaced the solenoid and the issue has been gone since.

Quotes source post: 20145670

@mrtrodonet Thanks for coming back to document the conclusion of this issue.... If you don't mind can you give a full account of the process you used to determine and fix the issue for others help others get to the results quicker ? Two years is along time to deal with this issue, but not too long in Porsche years...lol... Sorry I wasn't much help along the way. Your thread must of kept getting buried in all the threads about cup holders and best looking wheels ect... Glad you got it Solved !!!

Lets see if i can remember it all. 1) Fresh oil change with Driven DT40 2) Pull the plugs check condition, flip with the other side 3) Check coils, flip with the other side 4) Replaced crank position sensor 5) Check for bore scoring with endoscope (good luck seeing anything...LOL) oil analysis and other tricks One tail pipe is dirtier than other Ticking sound at cold, hot or all the time Oil consumption Smoke on startup Check oil if it smells like gas and is black color (carbon is getting from combustion) spark plugs black or have black residue 6) Gave up at this point since it was happening much less after replacing crank position sensor. Much later i noticed that valve lift solenoid was covered in oil and read more about it and decided to check it. - Pulled the solenoid out, cleaned with AFR sensor cleaner. - Tested with a 12v power-supply and found that it was not responding. Should make a click and move the little rod inside. - Ordered a new solenoid and a mounting bracket (the one with seal that goes around the solenoid) The tricky part was to notice that oil leak. Only discovered it when i was troubleshooting low oil pressure issue that i was having occasionally at idle on traffic lights in hot weather. Since we are at it here is my check list from the notes. Oil pressure issue troubleshooting in no particular order: Drop pan, check blockage (done) Low Temp thermostat (done) Changed Relief Spring/Piston (DONE) Verify idle is at 650-675 (done) Check 3.5+ bar at 5k rpm (done) Check radiators for debries (Clean radiators) and structural integrity (done) Turn on AC. It increases idle speed. (Done) Oil filter installed at 19ft/lb. Use Mann filter. (had twisted filter) (done) <- got better after fixing this but came back on a very hot day. Check oil pressure with mechanical gauge (Oil pressure sensor replace) Likely fine…skip Oil pressure sending unit. (look for jumping oil gauge arrow) mine was jumping often at idle Oil pressure sending unit was the problem. And was a PITA to unscrew. Need a quality low profile crow foot 19mm wrench.