Schocki

Have installed about a dozen of then never noted a difference and my customers neither. My GTS is quiet at all speeds and rpm's.

85euro928

I have a similar sound except it's most noticable when I'm cruising about 30mph with my foot off the pedal (like when going down a slight grade). I have a new WP, and checked everything I could with the PKT but couldn't find anything unusual. Figured it was normal. I'm also running the Gate racing belt. It may make the sound when I'm accelerating but I don't hear it over the engine and exhaust.

Landseer

A PKT! Its about time this cool upgrade has its own roll-off-the-tongue moniker.

FredR

How about a PuKiT?

Fred

SeanR

Now that I think about it, my car has been making a whining sounds after the PuKiT was installed. And here, all along, I thought it was that Rotrex supercharger.

Manfred

That describes what I hear on mine to a T.

fraggle

whenever I hear whining I ask my wife to stay home.

atari_st

So I took the font cover off so I could check the tensioner in action. Sure enough, it has the high pitch sound folks are talking about. I faintly hear the other noise I was looking for. I put the car back together and rumbling noise that is coming from the passenger side front cover is back. I give up.....I am going to drive it.

I have a video with sound....cant figure out how to upload.

PorKen

Note high pitched sound is under acceleration, not when idling.

Odd cam noises could be a broken cam gear spider/hub.

sendarius

My 89S4 made spectacularly loud metallic crunching noises from the right bank when I started it, and then the engine stopped.

I am suspecting a broken cam timing chain, completely unrelated to the PKT.

Now I am too depressed to open it up to take a look.

Oh well, maybe Colin's Triflow cams aren't all that far in my future after all.

atari_st

OK.. here is a video. The difference between the two is with everything off the front of the car versus everything back on. Now....the sound is still there even when I take the accessory belts off. I can hear a faint trace of the noise with the center belt cover removed...but really apparent when placed back on the car.

Now.....give me you best guesstimate?

BTW: It should read belt cover off.....not cam cover.

Ed Scherer

Uncanny resemblance to WWII V-1 buzz bomb (which had a resonant frequency of approximately 45 Hz); listen to this about 30 s in:




I was wondering what the sound of the belt might be: 24 crank teeth per revolution, right? So I think impacts of belt teeth on something would yield a sound at about 270 Hz, wouldn't it? (I.e., I can't explain what we're hearing. )

I assume when you had the covers off, you inspected them carefully for any signs of contact, right? I couldn't really hear the sound with the covers off.

Ed Scherer

One other thing (long shot); as I see you don't have the tensioner pivot arm bolt and related bracket, see a post on an issue related to a cover installation issue (and the post that it refers to). Perhaps the issue covered in those posts could actually lead to a deformed (until corrected) enough cover that contact with moving parts could result. Seems unlikely to me, but still worth consideration.

Ducman82

is it hitting the cover?

atari_st

I think its solved and I feel stupid. Stupid is as stupid does! So I decide to tear it back down to check under the cover. I thought what the heck....let me take one part off at a time just to see if I can catch it. Well....I think its the Air Pump after all. Shot a video with air pump belt off than put it back on. I am freaking sure I have done it before and swore it was not the air pump. I am feeling pretty sure thats it.

Thanks for all of those who provide advice, opinions, and crazy stuff that do not make any sense but is fun to read anyway!!!

I am about to start on the drivetrain. This is a complete restore which will include Paint and Interior.