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Showing results for tags 'aos'.
Found 13 results
Hi Everyone, I am intrigued. Attached is a photograph of an oil leak from the front of the engine of my 2010 Boxster S. The pics show the front upper and lower oil pan just below the front engine mount when the leak was at its worst. Of course this is the 3.4 DFI engine, the car is pristine and has only covered 33,000 kms. The history is that the leak was diagnosed as a faulty AOS at the last service a month ago and the AOS was changed. But the leak persisted, not a lot, occasionally a spot on the garage floor but not always. Looking from above and from behind the front seats the engine appeared to be completely dry above the upper oil pan. Also the PDK had become very sluggish and unpredictable when taking off from a standstill but otherwise the car appears to run fine. When I reported back to the dealer they advised that both problems were caused by the AOS. They said that the new AOS was a faulty part and happily agreed to replace at no cost. This has now been done and after a hot 250 km run the leak has stopped but there is still some oil residue around the lower pan. But nothing like in the attached picture. The dealer advises that this is oil leaking from the intakes left from the bad AOS and that it will clear over time. Miraculously the PDK is back to perfection so I guess the dealer knows his stuff. But does this make any sense?
My 1998 Boxster suddenly had hot start issues where if left in the sun here in Texas for a few hours would then crank but not fire unless you kept cranking and pressed the throttle. No issues when starting cold. It had thrown some evap leak codes a few times and a secondary AI once but nothing consistent and would also suffer from idle issues if hot start was hard. Having read many threads I decided that it was not fuel pressure related as in my experience fuel pumps either work or they do not and the same applies to the associated relay. I read someone blocked off the valve under the lhs air intake plenum and when I did this the hot start problem disappeared but gave other idle issues. I decided to replace this valve and in the process also decided to clean the throttle body and iacv when I discovered oil in the aos and j tube the aos was replaced 3 years ago. Having replaced the valve and the aos the car appears to be running better than ever. I had no white smoke issues or oil cap pressure test problems and the old valve was in the closed position when I removed it so that may not have been an issue. This whole situation had gone on for many weeks and also gave air leak codes in both banks but using a smoke generator revealed no issues.
I am starting to prepare my car for a track day at Chuckwalla valley raceway at the end of the month, and I was told that the car as it sits has oiling issues? My car is a 2003 Carrera. I bought the car last year with 74k miles and immediately did the following: LN IMS bearing, Waterpump, coil packs, spark plugs, all filters and fluids, clutch + flywheel and a stock AOS. In anticipation of the event, I am going to do an oil change from M1 0w-40 to the Joe Gibbs dt40 oil suggested by Jake Raby along with fresh filters. Is there anything else I need to do to not have oil starvation? Is this issue blown out of proportion? does the 2qt sump extension make that much of a difference? will it affect the streetability? I am running 200tw tires.
My 2004 Carrera coupe has developed a leak. It started after I flushed my cooling system. Rather sure it is around the AOS/associated lines. I've read various opinions about the difficulty of removing the AOS. But what I am interested in doing is just replacing those lines. Any experience or opinions on doing this? Specifically, is it even possible? Especially if this can be done without removing the intake manifold? Also I am only finding the upper oil separator coolant hose. What about the second one?
I'm looking for advice in maintaining my well kept 2000 Boxster. In 2003, I bought a 2000 base Boxster with 14,000 miles (manufactured 11/99, 2.7L, MT) from a Porsche dealer in Massachusetts, where I primarily reside. The car now has just under 40,000 miles. So I've only driven it 26,000 miles in 13 years, and I have had no major problems. I had maintenance done by the dealer initially for about 5 years, but then switched to a more local independent mechanic with a good reputation, as the dealer was over an hour's drive each way. Last year I bought a condo in Naples, FL, and decided to drive the car down and leave it there. My mechanic replaced the engine drive belt as a preventive measure before the drive south, and the car was excellent for the long ride. Other than that, over the years, I've mostly only had routine and timely oil changes, plugs, and filters. I replaced the top and the tires a couple of years ago. The CEL did come on at times about a year ago, but it could not be reliably diagnosed. The mechanic suspected an O2 sensor. But the light since went off and all seems well since. Sometimes I can get a puff of smoke when I start it, especially after it was sitting for an extended period, but this resolves when the car is driven more regularly. I believe I have a good storage protocol for the times the car is idle. In recent years, the AC has been declining. The mechanic added refrigerant periodically, which worked for perhaps a year at a time. I am due for that at least, if not more at this point, as there is no cold at all now. In Massachusetts, this was less of an issue, but now I want to get that more correctly resolved. The AC seems more noisy than it was previously (up front?), so I imagine there's a leak or other issue. Outside of the AC problem, the car is operating perfectly as far as I can tell. I drive it about 5 weeks a year while in Florida. It is in excellent cosmetic condition, barely a scratch, and always garaged. I'd like to continue to operate the car in this manner indefinitely for the next several years, and hope to spend increasingly more time (winter) in Florida as time passes. Does anyone have any advice for me as to how I should proceed with this car? It looks and drives like new. I'm not a mechanic. I hear and read about the IMS bearing, the AOS, and other issues. I've not had the brakes or clutch done, but they seem fine. Even the battery is from 2003 and the car starts right up. So I appreciate any advice moving forward. Should I have some of these things dealt with preemptively, instead of waiting for a more expensive failure? I'd like to bring the car in for maintenance and hope I can find a conscientious and competent mechanic to assist me. Does anyone have any recommendations for a local mechanic and/or the dealer in Naples? Would anyone recommend going to an "AC specialist" type place for that one particular issue over a mechanic or the dealer? Thanks, Paul.
Greetings RennTech Community, Seeking the best place at the lowest price to purchase an Air Oil Separator for my 2005 Carrera S 3.8. Pelican Part offers 99710703800 for $211 + Free Shipping but others have mentioned paying around $150+ for the 997.1 AOS. Can someone recommend where I can purchase it for the lowest price? Thank You, Stephan
My 2004 Targa has started leaking coolant. I've found the source, and it's the AOS. I called my local Porsche shop to get a replacement, and they only one they can get is the AOS that doesn't have any connections for coolant lines. Will this work in my car? If so, what do I do with those existing coolant lines that went to the old one? Thanks!
So I decided to take my 911 to work today since traffic is a lot lighter on Friday. Got about 12 miles into the 17 mile drive and started to notice a cloud of smoke behind me. Had to slow down and once I got below 3000 rpm it largely went away. Pulled off the highway and on the 1/3 mile drive between the highway and the the garage I noticed that there was a whine, kind of like a serpentine belt, when below 1500 rpm. Parked immediately. Called AAA and it took forever for the truck to come. Had to get the car out of the garage and it smoked again on startup but no whine. I'm hoping that this is just the AOS but am not sure. Any other ideas on what this might be?
albin posted a topic in 996 Series (Carrera, Carrera 4, Carrera 4S, Targa)I have a 996 3.4l (1999) tiptronic with 140'000km. The engine was rebuild at 80'000km and the tiptronic rebuild at 100'000km. I face a strange problem since many month. I try to explain symptom in chronological order. - When it rain during the night, I need to start two time the car. The car start alway from the first power on, but no power at all. I need just to power off and re power on and the car work fine. - One month after, the car is running on 4-5 cylinder after the second power on... lot of missfire. - The garagist change all 6 spark, 6 coil, the AOS (leak problem), the MAF and the two lamda probe... Now the car run almost good except: ans this is my question. Could you help? When i drive slowly (following car) between 1'500 and 2'000 rpm (rpm important) in 3 or 4 gear (tiptronic) and I would like to speed up to overtake a car, the engine do not ramp up rpm, lot of missfire, the gear do not swith to 2 quickly and accelerate...! When i accelerate from 3'000 to 6'000 no problem the car run very well. Now, the garage tell me it is a tiptronic problem...? Could you help me on the road to find a solution ? Thanks in advance
Sorry for the rant but just had to get it off my chest. My local dealership just quoted me 20 hours labor to change my AOS. '01, 996 tip, C2. Total estimate, $3300. I don't blame them for wanting to drop the engine but good grief, 20 hours to do it??
Has anyone ever broken the AOS Vent Line that goes under the intake plenum up to the front of the left side of the engine? Well I did it on Saturday taking out the AOS. A simple job turned into a nightmare. I couldn't find anyone online who has experienced this catastrophe, so I took it upon myself to explore where on earth did that line go to: I really was amazed at where it wound up. Not because of its location but how on earth can I route a new one? So far I have taken off the the AOS, Throttle, Alternator and the infamous Vent Line. I couldn't even find the part on Pelican or Suncoast which really scares me. Does anyone have some knowledge of this repair, How on earth can it go back without damage??? 2000 Boxster,986 Manual Trans, pretty much all stock, 140,000 miles.
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:
Alright, 2 weeks ago I bought an '03 996 Cabriolet from a physician friend of mine... After driving it for two weeks I noticed a large puddle of coolant on the garage floor. The coolant leak was coming from the back drivers side of the engine (pics to follow) After researching this topic thoroughly over the weekend I am confident that I can execute his repair myself... But first, let me stress to everyone that I AM NOT A MECHANIC, nor have I ever attempted any "mechanics" except for oil & filter changes. There are some really great write-ups that gave me the confidence and know-how to tackle this job. I'll be sure to give credit where it is due when this proj is complete... About the only thing I didn't find was a video documenting the process step-by-step so I figured this would be an excellent opportunity to make one and provide it to our forum community. Here it goes... Step-by-step diy video instructions soon to follow!!!!