An annoying squeak when engine cold!

[Gibbo205]

Hi there

When its particular cold, i.e. winter, my car at cold start has a squeak, like engine/auxilary belt. I had the belt changed at last service, less than 5000 miles ago and was hard to tell if it fixed or not at the time as it was Summer.

Well squeak is still there, sounds like a belt or one of the pulley's the belt is attached too. OPC have offered a free health check for my car and as its under warranty I was going to complain about this again and tell them not to bother changing the belt again as thats not it, most likely one of the pulleys the belt is one or something needs removing, greasing up and re-fitting.

Just wondered if there is a common known issue which causes this squeak on cold start up, once the car has been running a few minutes, the squeak goes away. Its nothing serious just a pain in the ass that a prestigue car like the 911 sounds like some battered squeaky French car on startup.

P.S. The squeak is only at idle when cold, hold the revs over 1200rpm, the squeak is gone, but at idle 750rpm the squeak is noticable from outside the car when engine within first 5 mins of being started. I can live with it but for sake of changing a pulley/belt I will change it to solve this niggling issue.

[vinnie83]

My car does the same thing on startup. I can't offer any advice into the reason why though!

[sneakybear]

I had the Water Pump replaced (warranty) a few months ago and along with it the belt - as it shredded when the pump broke.

Afterwards, for some time, it had a similar squeak on cold idle... went to the Alps for 3 weeks skiing (c.4500 km) and it's now fine.

Not much help I realise and agree on the nuisance and general annoyance expected with 14 year old French cars. If you find a solution please share!

Cheers,
sb

[gtphile]

Have a look at the condition of the idle pulleys, if they have rust spots on them, that can create a squeek, a bit of wire wool sorts it.

[Gibbo205]

gtphile said:

Have a look at the condition of the idle pulleys, if they have rust spots on them, that can create a squeek, a bit of wire wool sorts it.

Any chance you can post up an image for dummies with these idle pullies pointed out please and I shall take wire brush and give them a cleaning.

Car has pretty much always done it when cold, changed belt and obviously not that, mention it to Porsche and they just are a bit well, they do that sir when cold, mmmmmmm. My 15yr Jaaaag with nearly 150k miles don't squeak!

[gtphile]

I'll try after work, but you will have three idle pulleys near the alternator,one is actually mounted to the engine by means of the alternator bolt. They are black, and around 70mm in diameter

[Trev450]

Gibbo205 said:

Any chance you can post up an image for dummies with these idle pullies pointed out please and I shall take wire brush and give them a cleaning.

Nooooooooooooo

A wire brush is way too abrasive. Use wire wool or fine emery paper.

[Gibbo205]

Trev450 said:

Nooooooooooooo

A wire brush is way too abrasive. Use wire wool or fine emery paper.

OK, another question is it safe to spray some WD40 on the belt whilst running to see if the squeak goes? I ask because it would rule out the belt?

[Rockster]

Gibbo205 said:

Hi there

When its particular cold, i.e. winter, my car at cold start has a squeak, like engine/auxilary belt. I had the belt changed at last service, less than 5000 miles ago and was hard to tell if it fixed or not at the time as it was Summer.

Well squeak is still there, sounds like a belt or one of the pulley's the belt is attached too. OPC have offered a free health check for my car and as its under warranty I was going to complain about this again and tell them not to bother changing the belt again as thats not it, most likely one of the pulleys the belt is one or something needs removing, greasing up and re-fitting.

Just wondered if there is a common known issue which causes this squeak on cold start up, once the car has been running a few minutes, the squeak goes away. Its nothing serious just a pain in the ass that a prestigue car like the 911 sounds like some battered squeaky French car on startup.

P.S. The squeak is only at idle when cold, hold the revs over 1200rpm, the squeak is gone, but at idle 750rpm the squeak is noticable from outside the car when engine within first 5 mins of being started. I can live with it but for sake of changing a pulley/belt I will change it to solve this niggling issue.

The car is under warranty. Take it in and detail how to reproduce the noise -- write it down and proof read it -- and let the tech reproduce the noise and diagnose the cause and fix the cause.

Why try to diagnose this yourself? Beside even if someone guesses right what's going on you or a tech is going to have to get his hands dirty repairing the car.

Last but not least I'd no more use WD 40 on a "squeaking" serpentine belt than I would on squeaking brakes.

[Trev450]

Gibbo205 said:

Trev450 said:

Nooooooooooooo

A wire brush is way too abrasive. Use wire wool or fine emery paper.

OK, another question is it safe to spray some WD40 on the belt whilst running to see if the squeak goes? I ask because it would rule out the belt?

Don't use WD40, but water will have the same result.

[Rockster]

Trev450 said:

Don't use WD40, but water will have the same result.

Don't think so. When I get water on my 996's belt it slips/squeaks (chirps anyhow) until it is dry.

The serpentine belt should be dry and clean and silent.

If in the case of the OP's car if the belt is the source of the noise -- the belt proper or an accessory drive or an idler roller bearing or tensioner roller bearing -- the source needs to be id'd and fixed.

[Gibbo205]

Rockster said:

Don't think so. When I get water on my 996's belt it slips/squeaks (chirps anyhow) until it is dry.

The serpentine belt should be dry and clean and silent.

If in the case of the OP's car if the belt is the source of the noise -- the belt proper or an accessory drive or an idler roller bearing or tensioner roller bearing -- the source needs to be id'd and fixed.

Are you saying it's ok to spray the belt or saying definitely not too?

I'd have personally though spraying the belt is probably a bad idea as like you say it will make it slippery and no doubt slip/squeak?

Maybe better to direct WD40 at the pulleys where they connect into the engine to clear out any dirt and moisture whilst being sure to avoid the belt?

[vinnie83]

My car only does it for under a minute when first started from cold - it really isn't enough of a problem to bother me... does yours continue to make the noise for long?

[turk1]

If your car is under warranty then let them sort it out, But if you can't be bothered just spray some WD40 on the pulleys and that will stop the squeaking for now, I had the same problem and that's what I did,but the squeaking will come back over time, just try not to get none on the belt.

[Rockster]

Gibbo205 said:

Are you saying it's ok to spray the belt or saying definitely not too?

I'd have personally though spraying the belt is probably a bad idea as like you say it will make it slippery and no doubt slip/squeak?

Maybe better to direct WD40 at the pulleys where they connect into the engine to clear out any dirt and moisture whilst being sure to avoid the belt?

Sorry I wasn't clear.

I'm saying it is *not* ok to spray water or anything else on the belt or pulleys.

In my previous post I was talking from the context of when my car in this case the 996 Turbo sits out in the rain or when I wash the car and the water runs down through the louver openings in the engine compartment cover and gets on the belt/pulleys and sometimes on the coils for they have misfired once or twice.

There is nothing to be gained by spraying anything at any accessory drive shaft/seal interface since there is nothing that can collect there that can account for the noise.

If there is any signs of grease, fluid, or coolant leaking at the seal/shaft interface -- which is hard to see -- it is a sign the seal/bearing is going bad and this should be fixed.

Generally the accessory drive is replaced, as would be the case if the water pump was the culprit. The alternator might be rebuildable. Thankfully I have not needed to delve into this question. Other accessory drives I have no idea. Accessory drives have proved to be quite reliable in my Porsches the only one failing was the water pump at around 172K miles.

[Gibbo205]

Hi there

Well had a look tonight started up, squeak squeak whilst cold. Open engine compartment and some snow/water fell on the belt and the noise went for a few seconds.

So strategically sprayed small amount of WD40 behind each pulley, when I sprayed behind tensioner pulley it went quiet, sprayed more it went completely.

Looks like a new tensioner pulley it is I suspect.

[Gibbo205]

This is a 996 3.4 motor, I'm assuming pulley layout is the same?




Hitting the back of number 7 (tensioner pulley) with WD40 cured the squeaking.

[Rockster]

Gibbo205 said:

This is a 996 3.4 motor, I'm assuming pulley layout is the same?




Hitting the back of number 7 (tensioner pulley) with WD40 cured the squeaking.

Don't know about the similarity but the idler roller between the 3.4l and 3.6l engines but it was the uppermost idler roller in my 996 Turbo that started making noises -- not squeaks though -- that prompted me to have the noise looked into and the tech replaced the noisy roller under CPO warranty.

[Chrisp5782]

Gibbo205 said:

Hi there

Well had a look tonight started up, squeak squeak whilst cold. Open engine compartment and some snow/water fell on the belt and the noise went for a few seconds.

So strategically sprayed small amount of WD40 behind each pulley, when I sprayed behind tensioner pulley it went quiet, sprayed more it went completely.

Looks like a new tensioner pulley it is I suspect.

So after being advised not to spray
WD 40 at the pulley / belt you did it anyway?

What ever you do don't sell me your car for a tenner.

(Gotta be worth a try?)

[Gibbo205]

Chrisp5782 said:

So after being advised not to spray
WD 40 at the pulley / belt you did it anyway?

What ever you do don't sell me your car for a tenner.

(Gotta be worth a try?)

I was told not to spray the belt!
Spraying the pulley with a small amount trying to locate the issue is fine, it's allowed me to pinpoint the source of the problem in less than 5 minutes and now I know which part to replace and whilst it's being done shall get the belt done too.