Discouraged

I spent the whole weekend cleaning out my intake. I've replaced my AOS, plugs, coils and starter just recently. Today I noticed my car running a little rough on the way home from work. Then when I stopped for gas, the oil said it was low. It was down about 2/3rds from where it was yesterday. I got home and checked the air lines in my AOS and they were full of oil again. What the hell man? Can an AOS be bad out of the box? Is there another problem that makes an AOS go bad in one week? Are Porsches just unfixable? This is highly discouraging.

I am far from being a expert with any of this stuff. but I can certainly try and lend a hand here. First off you did not say if you replaced the AOS because it had gone bad or were being proactive. Did you replace the AOS related hoses or just clean them out? From what I understand if the AOS was bad you can have a lot of oil throughout that entire system. I am thinking you might have oil in places you did not clean and it has migrated into the cleaned or replaced lines. It is highly unlikely that the new AOS is bad. You can do a simple check for that. With the car running open the oil filler cap. It should open freely without any vacuum resisting removing the cap. Did you replace the plugs before you replaced the AOS? Meaning did you replace the plugs one weekend and the AOS the next ? Or something like that. If so could you have fouled the new plugs with a bad AOS before replacing the AOS. Or did you do the AOS first then the plugs? A fouled plug or two will cause the engine to be a bit rough. If the AOS was bad it can foul the cats. Even before getting a CEL from fouled cats the car can start to run rough. The last thing I can offer is: I know that my oil level reading can vary by even a few bars. I can check it with the car cold sitting in my driveway. I will then check it again later having not run or moved the car and get a different reading. Then i will drive the car, check it again and get another different reading. It used to make me nuts. I would have thought that the reading should be exactly the same. But it never is. It goes down and even up!!! I have been told that as long as it reads in the safe range not to worry about the inconsistent readings. And these cars are far from unfixable. Like many performance cars they can be a bit fussy and they have their own quirks. It takes time to learn them and address them. Don't be discouraged. These cars are essentially very reliable. It is a good idea to find yourself a good indy shop that REALLY knows these cars. Obviously less expensive to be a DIY'er. But sometimes a good shop can be a lifesaver. And having one can give you a high level of comfort and peace of mind.

Thanks for the reply Ducatiguy, I did disassemble the entire intake and clean it thoroughly just 2 days ago. I replaced my AOS then did my plugs and coils, then did my massive disassembly and cleaning. It ran so great and then after 2 days it started to stumble again and oil was back in all the lines. I ordered a Uro AOS so that might be the problem. I have ordered a Porsche certified part this time and spent twice as much. Hopefully it is not just the same part. That is good to know about the oil level sensor. I hate electronic sensors and I am jealous of all those Boxster owners with a physical dipstick. What do you think of this video? The sucking sounds are pronounced and the engine even changes idle when you remove the oil cap. Is my 1 week old AOS bad? AOS POS video

Sorry mate, hang in there!

Check out the carnage boys. It's nice that the oil doesn't reach the MAF though. That is something. I have to wait almost 2 weeks for my damned parts to come in so I am tinkering in the mean time.

What parts are you getting? What did you determine to be the problem?

Oh and just a quick note, Pelican Parts changed my shipping for me and the part should arrive tomorrow. I love their customer service. I might have a drivable Porsche for the weekend.

Well the title of this thread is officially opposite as of now. I'm feeling optimistic. I have my new AOS on the way and arriving tomorrow and the engine is all cleaned and ready for the new part. Zip that in tomorrow and I'll have my Porsche back.

mainsoda, the URO AOS didn't get good reviews on some of the parts websites when I was shopping for a new AOS. generally my rule is if its anything to do with engine or trans - go original (only one exception - spark plugs). however do take note of ducatiguy's recommendation to check the hoses again just in case its something else. older cars need some kinks sorted out from time to time... speedy recovery for your ride!

Strangely it is good to hear that I'm not the only one that had problems with the URO AOS. I have high hopes that this will solve my issue. I am having withdrawals from not driving my Porsche for a whole week.

Update: According to FedEx, overnight means 4 days. Glad I paid all that extra money

Alright, intake clean, AOS that says "Germany" on the side installed and the car is running absolutely great. A fairly nice puff of smoke to clean out the oil from the bad URO AOS and it cleared right up. I also noticed that the one that originally came with my car was also aftermarket and not genuine Porsche . Using genuine Porsche parts has become something that I will very much take into account from now on.

For what it’s worth, yours is the second or third confirmed time that I’ve read about an AOS being faulty out of the box.

Good to know! Do you know if any of these were a genuine Porsche AOS?

URO = U Replace Often... seriously :-( You may also want to check the accordion hose that connects the AOS to the case breather behind the driver's side these are very fragile and dry too quicly..

Update: After 950 miles of my car running great and throwing zero codes I cracked my engine cover off today. Of course there is oil in the AOS lines and the intake. Not very much, but some. I have new hoses on order and will try popping those in, but I am just going to accept the fact that no AOS on my Porsche will every truly work perfectly and I'm going to stop worrying about it and just drive it.

is it less than with the URO AOS? according to my local indy tech, there is usually some amount of oil in most Porsches... as long as its not too much or cause smoking/leaking issues or consuming oil.

It is a lot less. The car runs great. In fact I just did an oil change and it seems like a very happy engine, no smoke out of the tail pipes. Maybe this is like the oil level sensor, close is good enough?

well that's good news....keep monitoring just in case though. enjoy in good health!