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Hello all, This is a continuing repair to what started as a camshaft deviation out of spec leading to the replacement of the chain tensioner pads / brake pads / chain ramps on my 2000 911 - 996 5-Chain engine. Seen here: That odyssey has since been resolved but I now have a new issue. Quick background: Removed camshafts, readjusted the camshaft chain timing "marker" positions, replaced tensioner pads, reassembled everything per factory specs. On first start up got very rough idle and bad misfires. At first I thought it may have been my timing was off but went back and visually inspected all and all looked correct (visually). Upon further inspection realized parts guy had given me Bosch 7403 plugs instead of Bosch 7413 (2000 Porsche 911). Current issue: Switched out and installed the correct spark plugs and no more continuous misfires / backfires. Did the initial reset (wait 1 min with ignition on / turn ignition off / wait 10 sec) On the first start up it did misfired / back fired once but I assumed that was left over fuel. Car now runs but very rough and threw 2 codes: - P0300 : Porsche Fault code 62 - Misfire damaging cat. converter - P0301 : Porsche fault code Cylinder 1 misfire damaging to cat. converter Also, took these readings: Actual angle for camshaft bank 1: -12.53 Actual angle for camshaft bank 2: 3.05 On positive note the main reason for doing all this work was the original problem / issue of tensioner / brake pad wear which was giving me a -10 / -2.92 reading is now: Camshaft position 1 deviation: 0.00 Camshaft position 2 deviation: 0.00 So the question is now are the Actual angle for camshaft readings within specs and could incorrect timing be attributed to these new issues? And... Do I have to give the DME time to "relearn"? Txs all
I'll start with a picture to make it more interesting to keep reading. ;) It's a '98 996 C2 manual with M030 and M220 (LSD), with 98k miles on it. Pic related, it's me under breaking at a track-day the 1st of June. The friday was ok most of the day, passed a GT3, tried to hold a GT2, but lost about a second per (2,3 miles long) lap. Always fun to pass or hold cars that are much faster, just on late breaking and good-ish lines ;) The CEL came on once on friday, but I calmed down my driving, pulled in and read out the codes: Multiple engine misfire (P03000), and three cylinder misfires, but I can't remember which cylinders. Did a quick check around the engine, everything looked ok, cleared the codes, started up, everything was ok, CEL didn't come back. Did a few more laps, still no CEL, the car pulled strong, no problems. Did the 20 minute drive back to the hotel, all was dandy. On saturday I pulled out on the track, did a calm round to get some heat in the tires, but the CEL came up after just a few turns. Calmed down the driving even more, but had unfortunately just passed the pit entry and planned on just driving a very slow lap to get off the track. Got half way down the start/finish stretch when the CEL-lamp blinked then stayed on steady. It felt like it was running on just 4 or 5 cylinders. I shut it down and coasted in a u-turn and drove the wrong way in the pitlane exit. Read out the codes, cylinder misfires was the only ones logged, but I got four cylinders this time so I ruled out problems with just one bank. Cleared the codes and, perhaps stupidly, fired it up again. No codes, no sounds, idle was fine, oil pressure normal, no warning lights, everything was like normal. Puzzled I shut it down and inspected some more. Found some fresh oil where the engine meets the gearbox, not a LOT, but enough to drip some drops to the ground. I figured that if this was IMS I'd hear the death rattle or have blown the engine by now so next on the list was RMS. Figured it couldn't destroy the engine and I didn't feel comfortable telling my insurance company that I needed a flatbed at a track, so I drove down to the main road. Car seemed fine, but lacking in power and shuddering above 3k rpm. Pulled out roadside and went back to have a final look around. If I blipped the throttle (to about 2,5k rpm) I could hear a faint rattle when the car came off the revs. Anways, luckily my insurance covers roadside assistance to the nearest _capable_ garage. We were currently in a small-ish town with the nearest Porsche Center in my home town, 400 miles away. I was convinced that no garage in that town would be dumb enough to start diagnosing a brand of car they'd never had in the shop, but flatbedding that kind of distance wasn't popular with the insurer. After two days of arguing they eventually towed it home. I got a rental the same day as the incedent and drove home. My local Porsche Centre started up not even a year ago and currently have just one Porsche mechanic. He's an experienced mechanic, and have the Porsche training, but naturally doesn't have a lot of experience with these cars yet. In fact, my 996 was the first 911 he did a service on at the new centre. After a quick look around he found what you're probably screaming at the screen right now: The AOS bellows was disintegrated. They replaced the bellows and washed away the oil, ran it on idle and didn't get any more oil. In fact, they said that my 996 was the driest they'd seen so far, with no oil sweat at all. So, RMS/IMS is out of the question. Either way, he heard a screeching noise and shut it down. No faults were registered. By now I had done my research and read up on what was, to me, a new frequent fault: AOS. I figured that if the bellows was that destroyed the AOS-unit was probably toast as well. As they are known to sometimes screech when they're broken, that might explain what he heard. I told the guy in the service desk about that, and that they also had to check for oil in the coolant and coolant in the oil. They did, and both liquids were fine. The mechanic though, described the sound more like scratching metal with a screwdriver. I've never heard an AOS unit go bad so I can't say if that's the sound it makes or not. The mechanic said he also felt the clutch pedal felt weird, and he wanted to pull down the gearbox to inspect the flywheel. They haven't swapped the AOS yet. He also went in with a boroscope to check the cylinders and said it didn't look excellent, with some scratches. But as this was the first 996 cylinders he'd seen he couldn't tell if it was normal or not. All six cylinders were the same, which is a good sign. The car wasn't low on oil. Even though I lost some at the track, I was still above the minimum mark. The problem now is that he's not sure what to do. Luckily, he's smarter than to do guesswork and throw parts at the car. They have a system where he can call other more experienced mechanics at other centres, but they are busy people and hard to get on the phone. The cars has been in the shop for more than three weeks now and I'm getting sick of driving around in a Legacy. Any good ideas here as to what might be going on? Are scratches on the cylinder walls normal for a 100k mile engine, and how much is too much? Also, not sure if it's related, but figured I'd put it in here: The steering made some screeching noises when I made my way from the track to the main road to drive back to the hotel on friday. It was just the first 2-3 minutes after starting up and I haven't heard or felt anything different since then. I also felt some juddering in the brakes on-track, but that's probably just warped rotors from track-abuse and heat. Brakes felt normal at normal speeds. Also, I noticed some Pentosin had spilled out of the reservoir up front. As I said, not sure if it's related. Give me your best guesswork, please. The not so pretty sight on saturday:
I have an unusual buzzing noise coming from the instrument cluster area on my 2000 Carrera 4 with white dials. I know there is a TSB from Porsche but it seems like it is for the 997's. I can not tell if it is air related or from an electronic buzzer. The buzzing noise occurs at about 75MPH and above. It is inconsistent, sometimes it will start at 75MPH and other times at 83 or 85 MPH. Based on the inconsistency and the sound, I am thinking it could be wind related, but how is wind making its way to the cluster? It sounds just like an electronic buzzer and I noticed something that looks like a buzzer on the back of the instrument cluster when I changed some bulbs a month ago. Could this be a speed related alarm? It is very annoying and I don't know where to start; I appreciate any advice. If this does not sound familiar to anyone, perhaps I can try and create a video of the problem and post it.