986s Squeaking at idle.. Light Hissing.. Oil cap stuck on.. AOS?

[HammerESQ]

2000 Boxster S (3.2)

6 Speed

77,000 Miles

Last week I noticed an issue that my 2000 Boxster S was beginning to make a squeaking noise at startup. It would squeak for a minute or two and then stop. I assumed I was looking at an issue with a waterpump or a bad pulley, and figured I would start digging into the issue this weekend.

Today (first time since I first noticed the squeak) I decided to drive the Boxster about 10 miles to the office and see if I still had a squeak. I did, but this time I noticed that it was constant at idle. I turned around to limp the car home and further investigate.

Symptoms are:

* Aforementioned squeak at idle, which now seems intermittent again.

* Oil cap is impossible to remove without tools with the car running.

* For the briefest of moments I saw an oil pressure light flash at idle while troubleshooting.

Everything I have read online seems to point to the AOS, but I don't have an abnormal amount of smoke at startup. Is this common? Are there any other ways to troubleshoot the AOS before throwing parts at the problem? Are there any other parts that I should order in addition to the AOS? I've read on some other posts that it's a good idea to replace the oil fill tube at the same time because it has been stressed by the vacuum created by the failed AOS?

Any additional tips/tricks to performing the replacement would also be greatly appreciated.

Thanks,

Hammer

[Beelzy]

The smoke is the last piece of the AOS saga, you have all of the other classic symptoms. I have heard the same advice about

the filler tube as well.

You might check to see if the oil level has dropped at all, that oil if the AOS is defective has to go somewhere.

Good Luck. :)

[1schoir]

2000 Boxster S (3.2)

6 Speed

77,000 Miles

Last week I noticed an issue that my 2000 Boxster S was beginning to make a squeaking noise at startup. It would squeak for a minute or two and then stop. I assumed I was looking at an issue with a waterpump or a bad pulley, and figured I would start digging into the issue this weekend.

Today (first time since I first noticed the squeak) I decided to drive the Boxster about 10 miles to the office and see if I still had a squeak. I did, but this time I noticed that it was constant at idle. I turned around to limp the car home and further investigate.

Symptoms are:

* Aforementioned squeak at idle, which now seems intermittent again.

* Oil cap is impossible to remove without tools with the car running.

* For the briefest of moments I saw an oil pressure light flash at idle while troubleshooting.

Everything I have read online seems to point to the AOS, but I don't have an abnormal amount of smoke at startup. Is this common? Are there any other ways to troubleshoot the AOS before throwing parts at the problem? Are there any other parts that I should order in addition to the AOS? I've read on some other posts that it's a good idea to replace the oil fill tube at the same time because it has been stressed by the vacuum created by the failed AOS?

Any additional tips/tricks to performing the replacement would also be greatly appreciated.

Thanks,

Hammer

Hammer:

Those are definitely the classic symptoms of a failing AOS.

First of all, if you have the old style AOS (i.e., the top circular part is horizontal rather than vertical) then you should replace it anyway, IMHO.

Here are two photos to illustrate the difference:

OLD STYLE:

NEW STYLE:

If it fails completely, you run the risk of doing engine damage because the oil will migrate and cause something known as hydrolock.

You should also replace the j tube ( or "y" tube if your car is an e-gas car).

With respect to the oil filler tube, if it has no signs of kinks or having collapsed, IMO it's not necessary to replace it. IIRC that filler tube consists of three sections.

Regards, Maurice.

Edited October 7, 2008 by 1schoir

[slotsmd]

Reading your description I wonder if I am early on in the process of developing this problem. I have had my 2002 S for about two months now (41K miles). I'm getting pretty comfortable I didn't buy any problems, but I am always a bit paranoid after buying a used car. I did have it inspected, but it's still 6 years old and there are never any guarantees...

Anyway, I occasionally have a little white smoke in the morning when starting up. Also, it seems the coolant level is a little low; I added a pint of clear water a couple of weeks ago and have driven quite a bit since. Cold level in the reservoir seems down about a quarter inch. I took off the oil filler with engine running, and it came right off but I do hear a sucking sound. Oil level has held steady since I bought the car. Am I just being nervous or could this be a looming issue? If so, I am inclined to head it off and replace the AOS.

Thanks to anyone who can help...

John

[1schoir]

Reading your description I wonder if I am early on in the process of developing this problem. I have had my 2002 S for about two months now (41K miles). I'm getting pretty comfortable I didn't buy any problems, but I am always a bit paranoid after buying a used car. I did have it inspected, but it's still 6 years old and there are never any guarantees...

Anyway, I occasionally have a little white smoke in the morning when starting up. Also, it seems the coolant level is a little low; I added a pint of clear water a couple of weeks ago and have driven quite a bit since. Cold level in the reservoir seems down about a quarter inch. I took off the oil filler with engine running, and it came right off but I do hear a sucking sound. Oil level has held steady since I bought the car. Am I just being nervous or could this be a looming issue? If so, I am inclined to head it off and replace the AOS.

Thanks to anyone who can help...

John

John:

If you plan on keeping the car for a while, and you have the old style AOS, it would be a good idea to replace it preemptively.

As far as the "being nervous", the little white smoke in the morning is perfectly normal for a horizontally opposed engine.

BTW if you are adding water to the coolant, it's a good idea to add distilled water rather than tap water.

Monitor the coolant level and see what develops.

Regards, Maurice.

[slotsmd]

Sorry, feel like I'm hijacking this thread. Is the correct AOS for a 2002 S P/N 996-107-023-04-M100? I'm looking on Pelican and it says that ought to be it up to engine #65X01419. The picture looks like what you've shown above for the new style. Also, what is the j tube?

Thanks again

[1schoir]

Sorry, feel like I'm hijacking this thread. Is the correct AOS for a 2002 S P/N 996-107-023-04-M100? I'm looking on Pelican and it says that ought to be it up to engine #65X01419. The picture looks like what you've shown above for the new style. Also, what is the j tube?

Thanks again

Not sure about the part number for your year Boxster S. The "J" tube is a tube that runs from the throttle body to the top of the AOS. It's only used on non-egas cars. I believe that the e-gas cars use a similar tube, but it turned into a "Y" tube. I don't have first hand experience with that change though, so maybe someone else can confirm this here.

Regards, Maurice.