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So here's my problem.
I've got a 2001 Boxster S with the factory 3.2L engine and ~70,000 miles. I bought the car in 2010 with 38,000 miles on it. I have it serviced regularly every 5,000 miles at the independent dealership, iAutohaus, where I bought it. They specialize in European luxury cars and I trust them as much as a person can trust a dealership, I guess.
My wife drove out Monday from Phoenix to Albuquerque with no issues. After spending the night at a friend's house, she left to drive on to her final destination in Santa Fe. After leaving her friend's house, she called me saying the CEL was flashing and the car was running really rough and had very little power. She was close to an Autozone so I had her take it there to have the codes read. She called me back saying it read a P0303, P0302, P0301, P0300, P0304, P0305, and P0306. Which I know are misfire codes, on every cylinder.
Well, while I was checking around to find a reputable Porsche mechanic in Albuquerque, I guess the Autozone salesman told her it was due to bad gas and to buy some fuel system cleaner and she'd be fine. I called her back to tell her what I had found mechanic wise, and she said she had driven it on to Santa Fe. She said it was fine as long as she stayed out of 6th gear and didn't rev the engine too much. I'm not real happy she did that.
She got it to a mechanic in Santa Fe and he initially checked the coil packs. After clearing the error codes, he said the misfire on cylinder 3 kept coming back. He swapped the coil packs but the problem stayed with cylinder 3 so he began to think maybe spark plugs. That didn't help either. A compression test showed very low compression on cylinder 3 and a leak down test showed it wouldn't hold pressure.
The mechanic is suspecting a broken valve spring, or worse, and is suggesting either a $4500 rebuild or find another engine.
But of course, I'm in Phoenix and the car is in Santa Fe. Oh, and my wife, she is still there too.
I guess I'm a little confused on how it can go from running fine one minute, to having misfires on every cylinder, to having no compression on cylinder 3. Although, I'm sure the fact that she drove it an extra 50 miles didn't help anything.
I'll be leaving Sunday to go pick up the car, and my wife. I'm am an experienced mechanic, just not fluent in Porsche so I'm not sure if I want to tackle this myself or not.
Do you have any suggestions on additional troubleshooting I could do or should I just start looking for a new engine?
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: