Chirp at Startup and Low RPM

[Baconaire]

1998 986 5 speed 77k Miles, Hardtop in Boston area:

Recently began hearing a chirp upon startup. At first I figured the starter. But I can also get it to chirp at about 1000RPM to 2000RPM whether in gear or in neutral. It definetly seems tied to engine RPM. Seems like left engine compartment but I could be worng. Car runs fine.

I replaced the polyrib belt this past fall. Also replace the coolant trank and was tuggin on the oil fill. But it does sound like a squeaky pulley or something. I have the hardtop on as its winter in NE and I run the car year round. So a little salty rust would not be a suprise. It's not the roof but I have not had the will or time to crack the engine compartment or crawl under the car to investigate.

I also have the squeaky clutch noise from the throwout bearing. So far I have done all my own work. But I am thinking I'll let a local mechanic do the clutch and throwout bearing soon since it involves droping the tranny. Eventhough my clutch is fine. I beleive its original. Should I just ball that squeak in with this new one and get it all fixed? Did I mention I'm cheap and a working stiff. I just love my Box.

I did read other posts and heard about the oil sperator and the starter. Any thoughts?

[Baconaire]

I just got home and did notice one final resolute chirp at shutdown. So am I right now with out actually getting into the engine compartment, I'm leaning toward the oil separator. It's defintly left rear chirp, loud whether in gear or not. This weekend if the weather cooperates I'll take the car apart and I think I will get the oil separator if I can tomorrow. Now the question becomes, what's a DIY for the Box. I read some 996 posts but no Box.

The 996 post sound like its a big pain. Should I just bite the bullet and ship her off to my trustworthy independant mechanic and have him do this and the clutch (which works fine but squeaks also). I plan on doing all my brakes as soon as weather allows. I got the zimmermans drilled rotors and pads ready to go. I'm confident I can handle that though I've never done a break job before.

And I need a hood. Like I tell everyone who says 'oooh a porsche', like I'm rich or a snob. I say I can either afford to own the car or pay someone to fix it, not both. I paid less for my box than you did for your new Civic or minivan. So I try to learn to do most of the work myself. So far I've done well but nothing major yet. So of its fun, some frustrating.

Sorry to cover so many topics. just haven't been here in while.

Thoughts appreciated. Looking to go cheap. See about post for specs.

Edited March 1, 2007 by Baconaire

[John V]

I just got home and did notice one final resolute chirp at shutdown. So am I right now with out actually getting into the engine compartment, I'm leaning toward the oil separator. It's defintly left rear chirp, loud whether in gear or not.

I have the same chirp, I believe. I can get it in gear or out, and it's getting worse. Pulling away from a stop I hear it rhythmically, over and over. I cannot get it to occur by shaking the motor, exhaust, wheel, nothing. It only happens when the engine is running. I removed the engine covers and it doesn't seem to be a pulley. Seems like the sound is loudest inside the driver's rear wheel well.

Any insight? What would the oil separator have to do with the noise?

[Baconaire]

I replaced my AOS for lack of another solution. The old one looked fine as did the belows. But there was a good amount of oil in the S tube and throttle body. While your at it I would clean the throttle body well, and may as well clean the idle control. I also cleaned the intake plenum but be careful not to lose a rag in the there.

Make sure your serpentine belt is not squeaking. Having that break would stink. Also check your pullies and altenator as they could also squeal.

My squeak is gone but I can't say for sure if it was the AOS. I now have a mysterious tick that is much like the sqeak. And I have Secondary Air CEL codes. So I'm not sure what's going on. But having been in your position I would definetly replace the AOS. I let my chirp go for a while and I may have fouled the secondary air system (I don't know). Take your time and clean the hose and the whole intake track while your at it. The car will run better when clean.

[John V]

I replaced my AOS for lack of another solution. The old one looked fine as did the belows. But there was a good amount of oil in the S tube and throttle body. While your at it I would clean the throttle body well, and may as well clean the idle control. I also cleaned the intake plenum but be careful not to lose a rag in the there.

Make sure your serpentine belt is not squeaking. Having that break would stink. Also check your pullies and altenator as they could also squeal.

My squeak is gone but I can't say for sure if it was the AOS. I now have a mysterious tick that is much like the sqeak. And I have Secondary Air CEL codes. So I'm not sure what's going on. But having been in your position I would definetly replace the AOS. I let my chirp go for a while and I may have fouled the secondary air system (I don't know). Take your time and clean the hose and the whole intake track while your at it. The car will run better when clean.

Check your plugs, mate. :)

[Baconaire]

Let me add a final follow up. It started with a squeak and after replacing the AOS and going nuts with continued secondary air CELs, and ticking from the engine-Today I retightened all 6 plugs and YAHOO the tick is gone. It all makes sense now. I had replaced the plugs before the winter. One worked loose and loose plug= secondary air leak and noise.

So to all that have a squeak, chirp, sqeal, or tick, check your plugs first! Its free. I still advocate frequent cleaning of the throttle bottle and other intake airways and controls but that'a another issue.

The one thing I don't get is why a loos plug did not seem to harm performance much if at all. I would think compression would be lost.

Anyway thanks to all here who helped. I could not do all my own work w/out Renntech (and a patient wife).

[Baconaire]

Check your plugs, mate. :)

As you were writting I was test driving after going through the plugs and coils. All is well the blasted tick is gone! Now onto the body work.