gray911

Help me figure out what this noise is. I can only hear it after engine is warm. Intermittent at idle. Fan not running. I can only hear it inside the car. I tried to listen with engine compartment open but cannot hear it from there. I have a sound clip video but you have to crank volume up or have good speakers to hear it. It is like a grinding/squealing. Passed by dealer to listen to it briefly. Didn't think it's from belts. HELP.

Palmbeacher

The dreaded Phantom IMS Failure Mode

Macster

I'm not as familiar with the DFI engines and how they sound so I'm on less well familiar ground, but the noise could be (could be) a water pump.

However, my (only) experience with a bad water pump with one of my Porsches is the noise was present from cold. One 'trick' I used to at least determine if the noise was from inside or outside the engine was to remove the serpentine belt and start the cold engine and let it idle long enough to confirm the noise's present or absence. It was absent (thank goodness) and a wiggle test of the various accessory drives found the water pump the only one with any noticable play, and even then it wasn't much. Another clue, though, was the belt had a sharp inner edge which arises from the belt rubbing due to misalignment which arises from the in this case the water pump's loose bearing.

You are really better off taking the car in and tell the techs how to reproduce the noise and let them listen. They will put the car in the air and from underneath listen and if necessary bring out a stethoscope and use this to as best they can pinpoint the location from where the noise is coming from.

Once this is known, then, the true cause of the noise is more easily determined.

If the noise is real, it will not get better the more you listen to it, it will not cure itself if someone accurately guesses its cause/source.

Sincerely,

Macster.

Slamuth

That is perplexing. I can understand your fixation though, I'd be the same way. I'm afraid I don't have any guesses though.

PasPar2

Any chance its the HPFP ? did you do the recall?

gray911

The HPFP was replaced 6 months ago (recall). Thanks.

Zeus993

My first thoughts too - HPFP. Is your A/C on? Unlinkely this time of year in St. Louis...

Added: DFI engines dont have an IMS... in fact they have 40% less parts than the M96/M97s.

ADias

These cars have many systems operating at a cold idle - emissions pumps/vanes, cooling pipes, etc. It can be a myriad of normal sounds going on.

gray911

Only notice it after reaching normal operating temp. Any DFI engine owners care to listen to their engine to see if this is normal. thanks.

fpb111

Transmission? Is it the same clutch in or out??

MICHAELWWW

Mine makes noises but not that one. wouldn't worry about it. Don't forget to post back what you find out.

gray911

Noise stays the same. I wonder why it is only present after engine has been at oprating temp. Not noticing it when warming it up or at cold start.

ADias

The sound I hear, pointed out in the video, is a short buzz, which seems to repeat every few seconds. It does not sound to me to come from the engine proper or rotational accessories. Could it be a pump, which pumps every few seconds, or a flap/vane opening/closing?

kouzman

i cannot understand the sound...

One of the things i have, however, is a chirping sound like a slipping belt when i warm up on idle... From what i have read it should be the water pump...

I will have the dealer check the water pump and the fuel pump just in case and fix if necessary...

Your best bet is to take the car back and try and replicate the sound at the dealer

997_rich

My hearing isn't good enough to hear the sounds but a few things to check:

stereo speakers... try unplugging them. maybe it's interference coming over the stereo amp (even if it's off) when the fuel pump comes on or something especially since you cannot hear the noise from outside the car or in the engine compartment this is plausible.

Does this car have the porsche sport exhaust? Maybe it's the internal flaps trying to close but obstructed?

Is this one of the cars where one initiates the oil level check by turning the key to the accessory position? Does the sound match or approximate this action?

Good luck!