Whining sound ? Cold weather

Yes I did a search and can�t seem to find help or feedback. 996 manual. When the weather starts getting cold, there is a deep whining sound when driving in the first couple of mins and sound goods away when car is totally warmed up (I do warm the car up before driving by the way). What fumbles me is the sounds gets louder when I brake and it�s not the brakes cause I also hear it when lightly revving the engine during stop at lights. Seems like it�s coming from the front or rear�hard to tell when in car. Brought it to the shop but the cars was warmed up so no symptoms. What is causing the deep whining sound?? HELP

leave the car overnight at the shop? could be throw out bearing - or a pulley bearing - aux air pump - or a million other things no I dont warm up the car....the manual says to start it and drive it and to NOT allow it to warm up at an idle -

Any more feedback?

I really don't have any suggestions or thoughts as to what could cause the whining. But . . . . DO NOT warm up your car by idling it. Drive it while it's cold. Keep the revs under 4K, and drive it normally. When it is warm, then drive it hard. I live in Chicago, and as the weather got colder, I experienced none of your issues. My suggestion -- leave it at your mechanic's overnight. Let him start it up in the morning. I'll bet it won't take him long to figue it out. larry

Your cold is different than mine but the easy replacement is the belt that might be old and struggling when hard and cold.

Does it sound like a small electric motor? Could be Secondary air injection valve.

Agree with the belt check first... Easy to take out and while you are in there, you can also check all the pulleys for bearing issues by spinning them. Winter is here so more people might see this as well. Good-luck!

Check the air pump as suggested above. The easiest way to confirm whether this is the issue is to just unplug the pump and start the car while cold. Shawn

It's air pump.

Is a loud secondary air injection pump a problem, or is it just the cold weather?

Thanks. Will keep you guys posted.

Or, if your wife or girlfriend are in the car when it's cold....whining?

no WHINERS!!

why not warm the car up on idle?

Did you check the pump before posting? The air pump is on the bottom left of the engine compartment opening. Do a search for other posts since there are youtube videos so you can hear the sounds others have made and be able to see the actual part making the noise. Then you can try verifying thats where the noise is from. If so easy deal.

Quotes source post: 8056224

When the car warms up the whining stops. When my GF warms up the whining gets louder.

Quotes source post: 8056335

Borrowed from Worf928 and the Cayenne Forum: Modern engine management systems have a 'cold-start' feature that keeps the idle high and the fuel mixture rich until the coolant temperature in the engine block reaches a minimum temperature. (Older systems used a 'timer'.) At this point the idle and fuel mixture will drop to near normal and the oxygen sensor loop is engaged to begin driving the air-fuel mixture stoichiometric for emissions. The engine isn't really at operating temperature until the thermostat opens. Actually, it isn't 'warm' until the engine oil is warm. If you have an oil pressure gauge you will know that the engine is warm once you see the oil pressure drop at idle. Typical pressure is 4 BAR+ when cold and 2 to 3 BAR when warm. Engine wear is greatest at startup due to oiling - or lack thereof. Wear is next greatest during warm up because the various parts of the engine all have different heat expansion characteristics - gaps between parts are smaller or larger than they are when warm. The various parts are designed to have the correct size relationships when warm. For example an aluminium engine block expands more per degree of temperature rise than steel pistons in the cylinder bores. Thus, when cold the pistons are 'too big.' (Obviously that example discounts piston rings etc. but the general gist is the same.) An engine under load will warm up far more quickly than an engine idling. Thus, the recommendation to avoid cold idling: engine wear. There is usually an additional recommendation: use engine 'break-in' driving limits until the engine oil is warm. Once the engine oil is near operating temperature (say 170 degrees F) the engine parts are at their 'designed size.' Minimize engine wear by not cold idling the motor and driving moderately until the oil is warm.

It also doesn't pay to be going to the high heats with no real good flows of oil to keep dryer areas from backing on thin coats of dirty oil Unless its a chineese parts car then season the engine just like a wok.

Quotes source post: 8056414

[Image-only post; no author-written text. Original image references:] https://rennlist.com/forums/graemlins/rockon.gif https://rennlist.com/forums/graemlins/rockon.gif https://rennlist.com/forums/graemlins/rockon.gif

Quotes source post: 8056335

There several points of view on this. Obtaining full warmup up at idle is very wasteful, so I'd not recommend that. Many automakers recommend driving away immediately after engine start, though keeping the rpms down until the engine/drivetrain has warmed up to operating temperature which in cold weather can 10 or 15 minutes or more depending upon the ambient temperature and type of driving. There's another reason for this recommendation. A considerable amount of pollution is generated after a cold engine start. To alleviate this most modern engines use secondary air injection to add extra air after the exhaust ports which provides enough oxygen to burn any unburned fuel that has made it out of the combustion chambers. There is some especially after a cold start. This burning in the exhaust heats the converters and gets them up to operating temperature quicker so the engine controller can go closed loop and better control emissions. By driving the converters can heat up quicker than they normally would and pollution is reduced and gas mileage can improve. Even driving a cold engine is better for gas mileage than just sitting with the engine idling for a minute or so. However, I do not like to drive away from a dead cold start in my Boxster (or Turbo) (nor any of my cars before these two cars). Both are equipped with a manual tranmission. Maybe if they were autos I might feel different. So I let the engines idle until the secondary air injection pump on the Boxster shuts off. I can hear this pump run -- sounds like a Hoover vacuum running in the distance. Takes about a minute maybe less maybe more, depends upon how cold it is, how cold the car is. The Turbo I can't hear the pump but the engine rpms drop and smooth out considerably -- as does the Boxster when the air pump shuts off -- so I take that as a "signal" the Turbo's air pump has shut off. I find both engines are very tractable and easy to drive if I let them warm up just this bit before driving off. They are less so if I try to drive off immediately after a cold start. Another thing with the Turbo is it has VarioCam Plus (variable valve timing and lift) and this is active after engine start and during some of the warmup time. My understanding is if I drive off with the engine cold the engine controller will switch between the low lift to the high lift lifters as rpms rise then switch back to the low lift lifters if for instance I stop at a light and engine rpms drop back to idle. To avoid this switching back and forth I opt to let the engine idle a bit until it smooths out and I believe the variable intake lift feature is less active. I do this to save wear/tear on the variable valve lift hardware, though Porsche claims to have tested this hardware through 250,000 cycles. I know there is the opinion that engine wear occurs when cold but I have been treating my Boxster's engine this way for over 236K miles now and have subjected it to more cold starts you can shake a stick out and the engine hasn't suffered from it as best as I can tell. With good oil and reasonable use this cold start wear is not an issue. Granted if someone lets the engine sit who knows how long between uses at some point after sitting long enough there will be marginal lubrication at some points and then engine wear occurs. The real cause is extended intervals between uses and not just the cold starting. Pick a technique you are comfortable with. Whatever, avoid high(er) engine speeds and loads until the engine and drivetrain has had time to come up to temperature. These engines take a bit of driving/running to get warm. Even on a mild day. I like to consider the engine "cold" until the coolant temperature needle has reached the 180 mark and remained there for some time and the Turbo's oil pressure gage at idle has dropped to around 2 bar. I know at this oil pressure level the oil's hot. And thus the engine is hot. Sincerely, Macster.

yes, not to threadjack, but how you warm up your car Macster, is about how I warm up mine. I do feel that it is important for all of the different metals in the engine to expand to their proper places before I put much load on it. And I never put any real load or rev it over 4000 before full operating temp.. to the point that i am probably obsessive about it. I could care less about whats better in regards to emissions. :-)

Ditto to Macaster.... I let my C4S warm until the pump shuts off. About a minute or 2....sometimes 3 if it's really cold.

My mistake, I thought this was a thread abotu yrou wife.

I know...the debate about warming up the P cars have been discussed many time before till no end. Its a matter of opinion and I always warm mine up, even in the summer time till idel is normal before driving. By the way, she is my GF not wife. LOL

Well, is there a topic that HASN'T been discussed many times before?? I am fairly new to this board, and ANY of the topics that you want to discuss will be new to me. If you get tired of the old threads, weave some new ones!!! In the interim, I enjoy reading them all. It just helps me get up to speed. I have only had my 996 for the past two months. The education that I've received in the past two months ------Priceless. larry

Any updates on this? I am getting the same issue but for just 2-3 seconds at cold start.

Quotes source post: 8055756

You're right if its coming from the little pump at the bottom left of the engine compartment. I think mine whines just because it wants a bigger pump in the turbo size. Generally the best bet is getting your head in the compartment and feeling around for whats touched that changes the noise. A rod (thin wooden dowel) against parts with the other end near ear is one method to isolate where a noise is coming from. Hint: don't stick it on moving parts.

Check your power steering fluid level.

Quotes source post: 8190252

When I first picked up my car a little over a year ago I'd get the power steering noise a little. I checked the fluid and it was still good so I took some out and replenished with new. Still had the sound. During the course of things I tried burping any possible bubbles out running the wheel to both extremes back and forth once in a while. Then one day the sound just stopped not even sure if it was the burping or not that stopped the noise. Oh well. No leaks at all. It just wanted to make noise I guess. Pretty sure it was air in the system though.