squawbum

NJS. I'd reconnect them if you can. It was designed that way for whatever reason. Seems like all the higher end after market separators have connections for coolant lines. Definitely not a scientific answer!

Manometer delivery is delayed. Frustrated!!

So I resthaft my son's golf clubs. Have a great day!

squawbum

Got the manometer today. The results are in.
5.x inches of H2O measured vacuum at oil filler during idle.
Looks like my AOS is operating fine. Vacuum pressure measures 5 at idle. That's the correct reading I think. Coincidentally I havent had any white smoke since I started this thread. Thanks for all the info and help!

Ahsai

Nice. What problem were you trying to track down again?

squawbum

Thanks! I was trying to track down a phantom! I actually think I'm over analyzing things and just need to enjoy my car. Honestly, reading these forums has made me schizo about everything on the engine.

I originally staryed this thread because I was getting some white smoke on startup and then got tons of it a couple times when parked on an incline with the nose down. Nose up and no smoke. But parked nose down and after being parked a while, I got special effects amounts of smoke on startup and it stopped pretty quickly. Then after reading the forums I decided to check the vacuum on oil fill tube. I thought it was massive amounts of vacuum but after measuring it is only 5 inches of water. So I'm okay and a lot of anxiety for nothing. I even bought a new AOS and some tools anticipating I'd need to do this job.

I havent had white smoke since I posted this and my oil level is just above halfway on the dipstick between min and max marks. It was just below the max around 500 miles ago when I did oil pan leak repair and oil/filter service. I always use Mobile 1 0W-40.

Im curious now how my consumption will be now that the white smoke hasn't appeared in a while.

Thanks and I just need to stop reading these forums and just enjoy my car!!. Thanks again all!

NJS_04_996

Good news Squawbum!

Yes, I think I will at least consider that option. Went ahead and picked up a longer piece of tubing to replace the one that was cut in half so at least I will have the option of hooking the coolant lines up, but without actually having to reach the AOS once everything is back in the engine and installed.

Macster

I've never noticed any difference in my Porsche engines smoking behavior regardless of how they are parked. All I notice, with the Boxster, is a difference in oil level. The Boxster oil level could probably be checked with the car on its side. The Turbo senses an out of level condition and refuses to measure the oil level.

The biggest factor I have observed that contributes to the propensity of either engine to smoke upon cold start is the amount of time the engine had run before it was shut off. If the engine did not run long enough to get up to full operating temperature then it is more likely to smoke upon its next cold start.

The 2nd factor is how I was driving the car before I shut the engine off. I seldom (as in almost never) push the car hard then just shut off the engine.

After a spirited drive which can include freeway run I drive the car easy for a while before shutting off the engine.

With the Turbo the owners manual calls for a 2 minute idle time to allow time for the turbos to shed some of their considerable heat load.

With the Boxster if the coolant temperature gage needle is about where the radiator fans should come on or if they are on or if the engine compartment fan is running I'll let the radiators fans come on then let then run until they shut off, or if running run until they shut off, or let the engine compartment fan shut off before I shut off the engine.

(The Turbo has a 2nd fuse installed in the fuse box which causes the engine compartment to run all the time the engine is on.)

But once in a while I'll come in to home in a bit of a hurry. The engine coolant temperature is not that high and the engine compartment fan is off. Usually the day is rather mild. I accelerate a bit in the driveway then coast into the car's parking space and often shut off the engine in just a few seconds (after making a quick scan over the dash to make sure everything's ok). In this case then the next cold engine start can have -- but again not always -- the engine smoking a bit.

(The Turbo never gets this treatment as I mentioned above I let the engine idle 2 minutes before shutting off the engine.)

The 3rd factor is the number of miles on the oil. Based on my usage as the oil approaches the 5K mile mark even though my driving style and my habits I have regarding how I drive and how I allow the engine some idle time before shutting off the engine the more likely the engine will smoke upon the next cold start.

Even then the smoking is rare. What has happened is there is no smoking for it seems forever, then there is some smoking. It catches me off guard in that I don't really bother to look for it but while letting the cold engine idle a bit I catch something out of the corner of my eye and then spot a cloud of oil smoke wafting away in the breeze. About this time I happen to check the odometer and almost always note the car is coming up on its 5K mile service interval. (I really pay more attention to the trip odometer the the odometer most of the time.)

BTW, I prefer to run both of my engines with the engine oil level -- measured with the oil hot (up to temperature hot) -- very near or at the MAX bar. Pretty much a sure thing that when the level drops enough -- 2 bars when measured hot -- I'll dump in a quart of oil to bring the level right back up.

As I think I touched upon in a previous post the techs I have talked to say smoking upon a cold start is quite common with new and used Porsche cars on the car lot. These cars see very little engine run time. The engine gets started and the car moved -- dealers love to shuffle/re-arrange cars -- and then shut off.

The techs tell me as long as the smoking is brief, over with as soon as it starts, the engine doesn't manifest any issues (like extreme rough running, varying idle speed) and the CEL remains dark the techs don't give the smoking a 2nd thought. This is pretty much what I learned to do though it is nice to have some "official" confirmation this is the right way to deal with this.

I can tell you after 3 failed AOS's if the AOS is bad you might get a stumble, hesitation off idle, a slightly varying idle speed (AOS #1), or a CEL which can appear concurrently with a bit of engine stumble (AOS #2), or nothing (AOS #3). What you will eventually see though is billowing oil smoke from the exhaust. (With my Boxster with its single exhaust the exhaust just smokes, but with a car with dual exhaust outlets one might one smoke more than the other. The AOS "favors" one bank over the other when it goes bad.) Regardless of the initial symptoms, or no symptoms, when the AOS goes bad, advances to this final stage of bad, the smoking doesn't stop. In this case shut the engine off and arrange for a tow because the AOS is toast.

Flat6 Innovations

I had two in a row that were bad this week. One failed after the first 52 mile test loop. Replaced it, and the new one was failed when it came out the box. It was actually worse than the first...

JTT

In your opinion Jake, is this a NOS issues from sitting on a shelf for 15+ yrs or manufacturing flaw?

It would truly suck to be a customer at the end of an hourly rate for removing and replacing an engine 3 times. Flip side it would equally suck as a business to pay a mechanic a flat rate three times and not be able to collect from customer due to a part flaw, which I"m betting Porsche doesn't cover with parts warranty.

Flat6 Innovations

No, these units are all recent manufacture, within 2 years.Some are a few months old. I had one where the factory forgot to glue the seams together, and I pulled it apart with my bare hands...

We try to find problems on our 104 mile test drives (52 miles X2)and if we are successful, thats best cased scenario. The worst case is the unit fails when the customer receives the car back, and he lives across country... Then it ruins my entire experience with them, that I worked a solid year to build.

Then, whats even worse is an experience I recently had, where the customer's local shop takes advantage of the scenario. Then this shop knows who is paying the bill, and takes advantage of that. A few weeks ago this happened, and the shop charged 1,200.00 labor to do the AOS job, and there was no choice but to pay this ridiculous rate thats TWICE as much as I charge.

This is another reason why I hate warranty crap, nothing about it is fair to us as the engine producer, especially when most of these parts are sold to us without warranty; yet, we have to place a warranty on them.

The only thing worse than this is someone having a "weak" AOS that hasn't completely failed, but leads to excess oil consumption. In this case the owner drives the car, glazes over the new cylinders, and then we have to make an invasive repair, only because the AOS failed. We can't make excuses, we just have to suck it up and deal with it. Luckily we avoid these issues through our test work upon completion, but these are among the things that make me hate doing business.

Nickshu

Are the motorsport AOS's better as far as quality and longevity? From reading this thread it seems that they might be worth the extra cost if they are better in quality (vs just being better for the g-forces of track use).

Flat6 Innovations

Not at all. I do not favor these units. I still have them d=fail, and I have also had them bad right out of the box. A lot of engines that we see that come here with failed rod and main bearings have these units fitted. I have stopped using them entirely.

Nickshu

Thanks. Interesting, why would they cause failed bottom end bearings? Higher crankcase pressure causing oil starvation?

DBJoe996

Since the AOS replacement job for a garage DIY'er is such a total PITA - I was wondering if someone has developed a AOS bench testing protocol such as pressure testing the coolant side and vacuum testing the AOS diaphragm side? Seems like the install and test run procedure is such a gamble with this part. I've done the replacement on mine and I never want to do that again! At least not with the engine in the car. Wow...that was one tough job for a stupid plastic engine part.

Flat6 Innovations

Its not that they cause the issues, but just a contributing factor, like all the other issues we see. Yes, high pressures during deceleration are the norm.

As for a testing protocol:

To test this unit you must be able to pull 28" of water column depression at around 80 CFM to replicate what the engine creates for AOS load.

Just this week I was given the go ahead by a major parts wholesaler to develop a flow bench to do this work, so we can provide 100% quality assurance on all their AOS units that are stocked.

Developing the bench won't be easy. I plan to finish it as soon as I finish my faultless timing chain stretch measurement tools, and my "tensioner arrestors". That should be July or so.

DBJoe996

That is awesome news Jake. I would be willing to pay extra $ for a "Raby Tested and Approved AOS", or from the vendor/wholesaler who advertises 100% QA on their stock.

I think it will also be interesting to see the failure rate of new out-of-the-box units.