Re: AOS Replacement Cost?

Any idea of labor hours/cost?

I replaced the AOS last year, but may be having issues with it now. I took my 2002 base with 140K miles in to the dealer after I experienced a vacumn/whine sound coming from each side of the rear wheels. Upon initial inspection by the service rep, (he unscrewed the oil cap and the engine sound changed dramatically), he suggested it may be something to do with the AOS. I inquired about the potential cost if it was the AOS, and he indicated the book had it listed at 13 hours labor.

My jaw just about hit the floor, as I replaced the AOS last year myself, and it took me (an average joe who can do some things mechanical) about 7 hours. I would think a professional could get this done in a couple hours, perhaps 4 on the outside.

Any thoughts and experience with cost for replacing the AOS?

BarryL
Dublin, CA
2002 base tip 140K miles

$178.50 at my indie in March of last year for parts and labor. The part was replaced to see if it would stop the puff of smoke in turn 5 & 6 on the Summit Point track, so no cleaning of the intake system was done. If the dealer takes apart the intake bits and cleans, I'd expect a larger labor charge. Alas, wound up replacing with the motorsports version which is a bit more involved, but did that myself, before I got the problem solved.

Dave - 06 987 S coupe SG/NL; gone (but still my first love): 03 986 AS/GG/BK;

Part is about $120.

Labor varies, from the 4+ hours it took me (including lots of prep time and head scratching) to likely less than half that for a pro.

But at, say $100/hr (whcih is very reasonable to start with) your guy charged you for 30 minutes. Thank him.

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

... we charge 2 hours plus the cost of the part.
In 13 hours they may be removing the complete intake including the plenums to have them cleaned (with a Q-Tip).
As long as you clean the throttle body and the tee from any standing oil, you can just reach into the plenums with a rag and pick up as much oil as possible.
Since the plenums turn vertical, eventually all of the oil will be carried into the combustion chambers and burned.
Any residual oil will burn off in a day or two.
Happy Boxstering,
Pedro

Pedro Bonilla
1998 Boxster 986 - 311,000+ miles: [www.PedrosGarage.com]
PCA National Club Racing Scrutineer - PCA National HPDE Instructor - PCA Technical Committee (Boxster/Cayman)

---

Racecar spelled backwards is Racecar

"Racing is life. Anything before or after is just waiting" ... Steve McQueen as Michael Delaney in "LeMans"

"If you wait, all that happens is that you get older"... Mario Andretti

"Being second is to be the first of the ones who lose" ... Ayrton Senna

It took me about 2 hours to replace one on my 2001. It was replaced before complete failure, so no cleaning was required. But I did pull the intake open for inspection, and that added maybe an hour on top of the 2 hours for replacement.

Quote
BarryL
Any idea of labor hours/cost?

I replaced the AOS last year, but may be having issues with it now. I took my 2002 base with 140K miles in to the dealer after I experienced a vacumn/whine sound coming from each side of the rear wheels. Upon initial inspection by the service rep, (he unscrewed the oil cap and the engine sound changed dramatically), he suggested it may be something to do with the AOS. I inquired about the potential cost if it was the AOS, and he indicated the book had it listed at 13 hours labor.

My jaw just about hit the floor, as I replaced the AOS last year myself, and it took me (an average joe who can do some things mechanical) about 7 hours. I would think a professional could get this done in a couple hours, perhaps 4 on the outside.

Any thoughts and experience with cost for replacing the AOS?

BarryL
Dublin, CA
2002 base tip 140K miles

intake is removed to clean, which frankly isn't necessary. After the AOS is replaced all that I found is needed (after going through this twice) is just a good drive with the engine getting good and warm, hot though you needn't worry about overheating. City driving, stop and go driving on a warm day with NO A/C should do it. While driving you want to hear the radiator fans cycle on and then off again and to add icing to the cake the engine compartment fan come on too. All of which means the engine coolant and the engine compartment and the intake got plenty warm and any residual oil on the intake walls got warm enough to run or be pulled into the engine where it was burned.

As for removing the oil filler tube cap and having the engine react, change its sound 'dramatically' that is normal behavior. The removal of the cap creates a big air intake leak -- unmetered/unmonitored air -- which causes the engine to run lean and rough. The DME will adapt in short order though. When the cap is put back on the tube and the leak goes away the engine will again react -- though maybe not so dramatically -- while the DME unlearns what it learned when the cap was removed.

To me there is not sufficient 'evidence' to really suspect the AOS at this point.

I wouldn't eliminate it entirely... even a new one can fail which is why there is a 2 year warranty on the thing.

Also, just a heads up. I sometimes get some pretty screwy off the wall or over the shoulder estimates. In one case -- I can't remember the amount now but it was about 3 times what I had expected -- the service manager quoted me a fluid/filter service for a Tip when in fact the car has a manual transmission.

Nothing sinster. But still I like a ballpark figure. If I need a firmer estimate a tech will make up the estimate if I ask.

The SM (or service reps) see a lot of cars and it is easy for them to get their cars, repair/service costs crossed.

Still, always get a written estimate and if you can call around before and get some feedback the estimate is in the ballpark.

As for the noise... is it present when the engine is started cold? If so, arrange to remove the serpentine belt -- carefully note its direction of rotation and routing -- then start the engine and see if the noise is still present.

If not then the noise is coming from something in the accessory drive area. It could be water pump (my experience) or a dry idler roller bearing (another source of some noise) or another accessory drive going bad.

If the noise is still present when the belt is removed, well, come back and let us know.

Sincerely,

MarcW.

Turned out to be the AOS and I was quoted a price of $688 to replace. A local indy in Dublin quoted me a price of a little under $400. Rather than have it towed 50 miles or take the chance of driving it back to Dublin, I decided to have the dealer do the work. So, the 13 hours of labor didn't end up being the case. I'll report back the final damage. Thanks for everyone who replied!

Barry

that covers the premature failure of the AOS.

Even if the work was done at an indy shop there should be a 2 year parts warranty on the new part provided it was bought through an authorized dealer parts department. I do not know what parts warranty the online/email/mail order houses have.

Sincerely,

MarcW.

Yes, the service rep was good about informing me about the warranty... I just had to provide a copy of the reciept. While they were into the engine area, they noticed a leak in a coolant check valve near the tip transmission, with a cost of $135 parts, $335 labor.. ouch. I hadn't noticed any fluid losses, so I am assuming they were able to locate the start of something. Part needed to be ordered from LA, so the car will be tied up for another day or so.

I just did mine. Took about an hour to take off and an hour to put on. I did not clean my throttle body, however.

whoops....I'm getting mixed up with replacing AOS with RMS....I went in originally because the AOS failed, then they told me the RMS was bad...and THEN I had the clutch replaced and IMS bearing replaced. Nevermind!



Edited 1 time(s). Last edit at 05/11/2012 01:59PM by boxsterd. (view changes)