Annoying squeak from engine area

[deanslist.us]

I did a search on squeaks and found nothing regarding this problem.

I have a 1999 996 C2, PSS9 Suspension, recent clutch job. I recently did a track day about three weeks ago, squeak showed up a week ago. Only did a total of 30 laps all day on a 1.4 mile 14-turn course.

Squeak happens slightly on startup, always in low range when taking off, low range in second, thrid, all the way up. once I get over 3000 rpms, the squeak goes away. Does it when hot, cold, etc.

Myself and the mechanics checked almost everything:

1. Thought it was the fan belt, removed the fan belt and it still squeaks

2. Thought it was bearings, did donuts in both directions, still squeaked the same

3. Occurs with or without A/C on.

4. Occurs with clutch depressed and up, in and out of gear.

5. All pulleys were checked out and are fine (of course since the squeak still occurred after removing the belt)

6. A quick rev on the engine will cause a quick version of the same squeak as well.

Sound is coming from undercarriage, rear passenger area. We had the rear end lifted, running, with two Porsche mechanics under it, and could not figure it out. We could reproduce the squeak by bogging the engine with the E-brake on at around 400-500 rpms. It is very consistent and does not go away..almost sounds like metal rubbing to produce a high pitched repetitive squeaking, then fades as the rpms go up.

Anyone have any ideas? Please?

Edited April 30, 2009 by deanslist.us

[wross996TT]

does the sound go away when the clutch pedal is depressed?

[dr914jr]

In the 996 and 986 compression gasses that are able to get by a loose spark plug will squeak as they are forced past the seals on the coil packs. I know how completely ridiculous this sounds but I've seen it on three completely different cars. The first time it took a full hour with a Boxster on the lift as I scorched my face using a stethoscope all over the bottom of the engine. Check the spark plugs to ensure they're tight. ;)

[deanslist.us]

wross996tt:

No sir it still makes the noise with the clutch pedal depressed...and I am starting to become depressed.

dr914jr:

That does sound absolutely crazy, but I am going to check them out first thing tomorrow morning...after it is cooled down. Would I be experiencing power loss? Because the car runs absolutely perfectly, no issues whatsoever...except the annoying squeak. If that is the case, I suppose it kind of makes sense, this morning I noticed that the sound is indeed a bit more loud after first start-up than at the end of my 18 mile commute. Perhaps metal expansion is causing the gaps to close a bit more?

Edited May 1, 2009 by deanslist.us

[phillipj]

In the 996 and 986 compression gasses that are able to get by a loose spark plug will squeak as they are forced past the seals on the coil packs. I know how completely ridiculous this sounds but I've seen it on three completely different cars. The first time it took a full hour with a Boxster on the lift as I scorched my face using a stethoscope all over the bottom of the engine. Check the spark plugs to ensure they're tight. ;)

+ 1. I will second that possibility. Is the sound more like a "chirp"? Does it seem to be coming from one side of the engine? I had this issue and one Dealership mechanic told me I needed a new engine :lol: :angry: :censored: :cursing:

Turns out it was a loose spark plug letting gases escape as Dr914jr says.

Edited May 1, 2009 by phillipj

[dr914jr]

I really hope this is the issue you're dealing with. In my experience the power loss is relatively unnoticeable probably due to the fact that your attention is focused on the annoying sound. Good luck!

[deanslist.us]

phillipj:

Wow, but then again not surprising. It is the mentality of many stealerships: "Can't figure it out...replace the motor." "No sir your warranty expired, $22,000 please."

dr914jr:

I really hope so too, I told a friend of mine here at work about your suggestion and he said if that fixes it, then you deserve a medal...I would have never figured that one out. And my attention has definitely been focused on that sound.

Edited May 1, 2009 by deanslist.us

[deanslist.us]

Well, I admit that I am completely surprised that my spark plugs (2 of them) were in fact loose, and now that they are tight the squeaking noise is gone. Thank you times a million :renntech:

[dr914jr]

Great!!