teebo2345

The dealership says all these things are normal, can anyone confirm?

On cold start the engine makes a very loud sound similar to a bucket of bolts being shaken or a chainsaw for 2-3 seconds. Happens when engine is cold but not if i cut the engine and restart.

Sometime when I start it cold some white smoke comes from the exhaust but clears up when warm.

If I don't completely fill the tank the gas gauge doesn't update. I have to fill the tank completely for it to update.

Burns 1 qt of oil every 750 miles.

The car is a cpo 2007 997.1 turbo with 62k miles.

Boeing 717

I dont have one of these cars but from what ive read on here the bucket of bolts sound is not uncommon and I think has to do with the gearing system in the engine that have very tight tolerances due to its racing heritage.

All flat 6's can smoke on startup, thats not unusual. Color of the smoke can give indications.

The 750 miles per quart does seem excessive to me, my 140,000 mile 964 turbo was burning about that amount and the valve guides were on their way out. But historically you will see wild variations in oil usage on 911 engines.

Macster

Generally whenever a dealer tells you something is normal that's either right or a variation of "they all do that" which can also be right.

"They all do that" applies to various mild idosyncracies these cars have arising from their design, performance and trade offs made.

But a comeback from you could be to ask the noise in this case be demo'd by having another similar car started under the same conditions, primarly cold I guess.

IOWs, to "that's normal" or "they all do that" you reply "show me".

A bit of noise, valve clatter which can be due to a bit of bleed down of various zero lash lfters, a bleed down of the chain tensioners, and the switcing over to the low lift and possibly changing the intake valve timing these latter two items courtesy of the VarioCam system, at engine start, is normal.

Now I have no direct experience with the 997 Turbo but have heard my 996 Turbo -- which shares basic engines with your 997 -- start often enough to believe there's something else at work regarding this startup noise and that is the engine's combustion at start up and shortly after is to put it plainly is a bit ragged.

I believe the combustion is within the acceptable range -- for this startup never results in misfires and the resuting CEL and associated error codes (save with two exceptions that arose due to extreme (wet/very damp) climatic conditions and I might add the startup was a bit different in these two cases in that it was rougher than usual, quite out of character) -- but the engine at first has the valve clatter I touched upon above but also it has another sound that can be I think explained by some well less than ideal combustion.

I believe it is related to the desire to get the converters warmed up as quickly as possible which wants to feed an exhaust rich in unburned fuel to the converters to help them heat up guickly.

While I hear these noises they are not scary noises or even mildly upsetting noises and they in no way put me off the car or the engine. It is just a characteristic.

Anyhow, depending upon various factors some engines will manifest a bit more of it than others.

As long as the noise appears only after the engine has been off quite a while though how much time this represents can vary from engine to engine and as long as the noise is of a very brief duration and there are no other signs of problems the noise is probably normal.

'course any change in the engine's noise or behavior or the presence of a CEL means something is not normal and needs prompt attention preferrably with as little engine running as possible until the source of the noise, behavior change or CEL is id'd and fixed.

As for oil consumption...

Oil consumption depends upon many factors, some of which are under your control and some that are not.

Some that are under your control are how long you allow the engine to go between oil changes, climatic conditions where you live/drive, how much idling time the engine does (and some owners would be surprised to know how much time idling a car engine spends...), if the car is subjected to high rpms.

While in your car's case the oil consumption is towards the higher end of the acceptable range it is not scary high.

What I like to remind owners is like fuel consumption, the price one pays for his car, and countless other things, oil consumption can vary and it is best to try to follow good engine hygiene and reasonable usage to reduce this but to not fret too much about it.

Do not let the fact your otherwise very fine car is diminished in your eyes by the fact it consumes a bit more oil than some other examples. There is always a engine that burns less oil than yours.

Oh, for the smoke it might be water vapor. A way to tell is water vapor disappates very quickly even with no breeze while smoke, oil smoke in particular, hangs together even if there is a breeze.

As with oil consumption some of the same factors play a role in the engine's tendency to smoke a bit upon startup. Water vapor is a fact of life and there's nothing you can do about it. (This assumes the coolant level is steady.)

I've asked the techs at various dealerships about smoking upon startup and they report they see alot of it. This arises from the cars there get started often but driven zilch.

The techs tell me that they note the smoke event, but as long as it is short lived, accompanied by no engine misbehavior, CEL, or inappropriate noises, they pay it no further mind.

Fuel tank level updating? I never fill my car's tank without fillng it to full -- relying upon the nozzle's auto shut off with the nozzle upside down to ensure consistent fill ups -- and the tank level has never failed to update and reflect the new fuel level.

However, I vaguely recall some issue about partial fillups being an issue in that the car's special fuel tank setup -- split tank with two disconnected basins to accomodate the front wheel drive diff -- can not recognize a fill up that doesn't bring the fuel level to over 1/2 tank to the point the miechanical fuel level sensor can then update the Ecu with the new fuel level.

Sincerely,

Macster.

djantlive

A puff of gray smoke is common for flat 6 engine. If the car smokes after 5 seconds of a cold start, your engine oil is leaking. Compress test can confirm if this is a serious issue. white smoke until warm up is normal.

1 qt every 750 mi is excessive. Usually it's 1 qt every 3k mi.

rattle sound isn't normal. you can ask dealer to start another car compare to yours.

never heard of a gas tank gauge issue.

i would recommend another dealer looking into these.

Boeing 717

Engine noise....page 2 has a video which may be helpful...
https://rennlist.com/forums/showthre...ferrerid=36572


Oil consumption
http://www.6speedonline.com/forums/9...-question.html

jhbrennan

From the owner's manual - sometimes you can get an inaccurate fuel gauge reading in this situation.

If a small quantity of fuel is added to a nearly empty fuel tank, the fuel gage cannot measure the added fuel accurately. The „remaining range“ readout will also be incorrect.

Zeus993

My take? I have been underwhelmed with the goofy problems these cars have. For example on my C2S, without the navigation the clock lost a couple minutes a week. The PCCB's would 'groan, every now and again. And starting up after a stall was a sketchy affair. With my TT, the engine rattles! WTF? And the driver's illuminated doorway flickers and the left side clear running light I have to go and give it a whack every now and again to get it to turn on. And when I put the top up, the right read small window occasionally fails to rise all the way up. So they're not perfect, they're not a Lexus or a Swiss army knife. But the sheer joy I get out of these cars FAR out weights their idiosyncrasies. I love these cars. But they're like owning a horse. You love them and work around their deficiencies. I wouldn't drive anything else. Gidyup.

Bob in NY

On cold start the engine makes a very loud sound similar to a bucket of bolts being shaken or a chainsaw for 2-3 seconds. Happens when engine is cold but not if i cut the engine and restart. (this happens when shutting off the engine not starting it but can be avoided if you shut it off with the clutch engaged)
Sometime when I start it cold some white smoke comes from the exhaust but clears up when warm. (this is true but not all the time. usually happens if you're moving the car around after running for less than a minute)
If I don't completely fill the tank the gas gauge doesn't update. I have to fill the tank completely for it to update.
(yes, this happens now and then but not all the time)Burns 1 qt of oil every 750 miles. (never, my engine uses less than a quart in 5000 miles)

My car has just over 25k and these issues are pretty minimal imo. The car you're looking at seems to have a lot of miles, I would keep looking.

512bb

These are not quirks, they are issues. In 4K of driving the car has not gone through any oil (it was tracked 4 times). It smoked only once upon start up, which is normal once in a while and certainly not a regular occurrence.

I am not sure what you mean by bucket of bolts, for example the dry clutch on Ducatis makes that bucket of bolts noise, however, the turbo should not, unless you have a light weight flywheel clutch combo without the dual mass flywheel and clutch springs to reduce some of the noise. Even then, it should not be a bucket of bolts.

My suggestion is what has been said before, go to as many places/dealerships and have them start the cars for you to get a sense for what is normal and what is not.

Good luck.

speed21

Reading OP's post i think he is referring to the sound of the engine when it is in its warm up phase with the cold start function active. The engine does sound much louder and once the cold start function kicks off the RPM's die back to idle and the engine note queitens along with that. I actually quite like the sound of the engine during the cold start phase because it has a real loud and crackly note about it. I wouldn't refer it as being a bucket of rattly bolts sound though, but to each his own interpretation there. Again i'm sure your dealer would have checked your concerns.

With the odd puff of white smoke, that's a normal trait although that said it's odd how you can go months between these events happening. I find it tends to happen more so in hot weather and only on a dead cold start where the car has been standing for some time. It can also happen after a hard run (again more so in hot weather) if you haven't idled the engine down for 30 seconds or so before switch off. I have my own theory what causes it and i'm pretty sure i'm right....but again to each his own. Anyway I'm sure your dealer has it all under control with their assessment of your car because if it was a faulty separator or something else sinister they would have it pegged and not allow you to drive off with the issue.....well one would would hope anyway.

Re the oil consumption, again this topic is not new. But from my own experience ( i was in that linked thread) in consultation with my service advisor we agreed to use a different grade oil in their list of Porsche recommended oil grades, and since that point my oil consumption is now back to virtually zero again. I think i mentioned my issue in that linked thread where my car only started to use oil after its first oil change at @ 7000kms which raised my suspicions on which grade of oil they used at the change. Evidently whatever oil they used was not the same grade the car was delivered with from the factory. So if you aren't satisfied with the rate of oil consumption i would get the oil changed with a different grade from the list which the dealer would have. More often than not they just use a selected grade of oil from their bulk drum which they decided was suitable for most of the Porsches they service rather than having select grades hanging around in small quantities. All that said, oil consumption will also vary depending upon your driving style and operating conditions.

With the fuel gauge i don't have any issue whatsoever so i cant comment on that.

Best.

Doc GTO

The car is CPO so if any of these issues gets worse, you are covered.

The 1 qt of oil every 750 seems a bit high but the other then that, pretty normal.

To prevent the white smoke at startup, I always let the car idle for a minute or 2 before I shut it off after driving on the street. For the track, I let it idle 4-5 minutes then shut it off. With that technique, I never have any white smoke at startup.

Glenmhor 1

13000 miles and mine makes noises cold and hot same as my mates GT3RS so I tend to ignore. I did manage to curb the smoke at start up on the same advice as above - let the car cool and idle for a few mins before ****ting off.

Without hijacking the OP's thread what oil pressure reading do you guys get on idle when oil and water are up to temp. After a good drive mine settles not quite half way between 1 and 2 bar on idle. Probably 1.2 or 1.3 bar.

Interested to hear from others.

Rob.

aa909

when warm my settles in around 1.5

Glenmhor 1

I take it when actually hot it idles slightly below 1.5, warm mine make 1.5 aswell.

Rob.

aa909

good question, will need to take a closer look but from what I've read 1.5 +/- is in the correct range

is there something in particular you are concerned about? has the idle pressure changed from before?