Good afterlunch, new member here with a 1999 996 Cab, 79k mi, manual trans, ocean blue metallic with saddle leather interior, Porsche Sport Design 18 inch wheels painted gold, K&N cold air kit, muffler bypass, and lowered 3 inches all around. I love this car! Resurrecting the car from a cracked head/intermix and am encountering some strange behavior. Running Shout detergent through the cooling system to clean out any residual oil, had disassembled and flushed all the cooling system hoses/rads when I first took the car off the road in 6/18, so the current flush is more for the engine block. The strange behavior consists of extremely high oil pressure (4.5 to 5 bar) even at idle, ragged idle with plug fouling and, if I blip the throttle to overcome the ragged idle, the engine rpm"s hang up at 3-4k rpm whereupon I immediately shut off the engine. Consequently, I can't run the engine long enough to get it up to operating temperature so that I can then drain the detergent mix from the cooling system. I've had the car since 2014 and whenever I changed plugs, the old plugs had a light tan appearance. When I had the engine apart, I de-carboned both heads and all piston tops. Upon reassembly, I put 5 gallons of fresh gas in the tank. Now when I pull the spark plugs they are fouled and sooty, so today I installed new NGK platinums but the idle was still ragged and the rpm's would still hang up at 3-4k if I blipped the throttle. When I pull the new plugs tomorrow, I expect they will be fouled. Today I also drained the fresh Castrol 20W50 oil and replaced with fresh Castrol 10W30 thinking that the 50W oil was causing the high oil pressure. Even with the 30W oil, the pressure was still 4.5 to 5 bar. Prior to the cracked head I ran 40W and had 1.5 bar oil pressure at idle and 3 to 4 bar in normal driving, but had read that 50W was preferable which is why I tried it. I also removed the oil pressure sensor and could hear a slight rattle when I shook it (not that that means anything) and have read that when they fail electrically you can get either a zero reading or an extremely high reading, so perhaps that issue is a s simple as a failed sensor. When I had the engine out and apart, I took the sump cover off and cleaned out the oil pickup tube and the swirl pots. I only found one small piece of gasket sealer, everything was clean as a whistle which was gratifying. I just pray that I didn't reassemble the pickup tube/swirl pots incorrectly resulting in the oil pressure issue, although I did them one at a time so as not to mix anything up, and they are very simple and straightforward to reassemble. I replaced the AOS and the oil cooler, could those be the culprits for the rpm and oil pressure issues respectively? One final comment, the throttle cable appears to have shrunk by about one quarter inch in the 16 months the car was idle, no matter how I route it, the throttle butterfly bell crank is about one quarter inch short of the stop. Even routed it through the clutch slave coil and under the fuel injector rail feed lines, no luck but it will idle raggedly between 6-700 rpm. Apologies for the long post, look forward to your collective wisdom, thanks!