Jump to content

Welcome to RennTech.org Community, Guest

There are many great features available to you once you register at RennTech.org
You are free to view posts here, but you must log in to reply to existing posts, or to start your own new topic. Like most online communities, there are costs involved to maintain a site like this - so we encourage our members to donate. All donations go to the costs operating and maintaining this site. We prefer that guests take part in our community and we offer a lot in return to those willing to join our corner of the Porsche world. This site is 99 percent member supported (less than 1 percent comes from advertising) - so please consider an annual donation to keep this site running.

Here are some of the features available - once you register at RennTech.org

  • View Classified Ads
  • DIY Tutorials
  • Porsche TSB Listings (limited)
  • VIN Decoder
  • Special Offers
  • OBD II P-Codes
  • Paint Codes
  • Registry
  • Videos System
  • View Reviews
  • and get rid of this welcome message

It takes just a few minutes to register, and it's FREE

Contributing Members also get these additional benefits:
(you become a Contributing Member by donating money to the operation of this site)

  • No ads - advertisements are removed
  • Access the Contributors Only Forum
  • Contributing Members Only Downloads
  • Send attachments with PMs
  • All image/file storage limits are substantially increased for all Contributing Members
  • Option Codes Lookup
  • VIN Option Lookups (limited)

968 Low Revs 'chirp'


Recommended Posts

My 1993 968 Coupe, bought used at 51,000 miles and now at about 90,000 miles, has an issue where any acceleration causes a loud chirping, or perhaps pinging (for lack of a better word) sound below about 1300 rpm, even in first gear off the line. Above these start-off revs, there is no detectable problem and performance seems normal. Belts and rollers were replaced at 60,000 mi, well before the problem began. I have recently replaced all filters, plugs, cap and rotor - and checked my timing and balance belts (perfect condition and tension) - no change whatsoever. I use only 93 Octane fuel - from a variety of sources - and have run my last two tanks with Techroline at the prescribed doses. Mobil 1 0W-40, with regular changes.

The only conditions which improve this somewhat are cold engine / very cold weather starts and the exact opposite, a hard-run up-to-temp engine. Is this ringing a bell for any of you experienced 968 wrenches out there? On my very short list are: Variocam, MAF.

Link to comment
Share on other sites

Loren,

I'll check but nothing changed when I removed the old plugs (about 15,000 miles use) and installed a new set. I use copper antiseize and check gap - a real stickler - so it's unlikely. However, I did not know this bit of wisdom and I will check for it. Thanks.

Peter

Link to comment
Share on other sites

you say any acceleration, but then say below 1300rpm - so, i assume this is only first gear, as i don't know how you could get into another gear below that rpm - does it do it above that rpm?

is the sound rhythmic?

does it do it sitting in the garage?

if yes in the garage, does it do it with your foot on the clutch?

Edited by flash968
Link to comment
Share on other sites

Yes, primarily first gear. But the same thing happens if I am rolling in second at 1000 and gently accelerate. Problem disappears above that rev level. It is not rhythmic, more of a screech that immediately stops as revs rise above idle. I can make it do it parked by blipping the throttle abruptly from idle, or by holding the brake and slightly briefly engaging the clutch enough to load the engine in the idle range. So, off clutch or on clutch makes no difference.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.