Jump to content

The RennTech.org community is Member supported!  Please consider an ANNUAL donation to help keep this site operating.
Click here to Donate

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)
Sign in to follow this  

Recommended Posts

At last we did the leak down test. It hard to give a clear diagnostic. The cylinder that was giving the problems was #5 so we started with this one. The air came out of the oil filler tube & the intake valves. My confusion comes when we did the same test on another cylinder #3 to be precise. And it did the same thing.

The compression number we got out of this cylinders on the tests we did a while back were 180psi on #5 and 220psi on #3.

This left me with more questions than answers.

Could it be the rings? Or a burned valve?

What test can I do so we could narrow down the problem? And get my car on the road again!

I miss my car!

I appreciate all the info you can give me thanks.

Share this post

Link to post
Share on other sites
    You can remove these ads by becoming a Contributing Member.

We have to remember that we did the test adding oil to cylinder 5 and the problem disappeared for a little bit. As soon as the oil got burned out the problem came back.

Share this post

Link to post
Share on other sites

I was thinking of getting the engine down and replacing the rings and every part that is worn on cylinder 5.

What do you think?

Thanks again for your feed back. Having a car like this in this country is not easy we don't have any kind of support

Share this post

Link to post
Share on other sites

I think the car had the flu.

Today I used it and the engine failure wasn't there. The check engine light didn't turn on. It had all the power it normally has.

How can this happen? Now it got me thinking it's better to do what Logray told me in this chat.

To use the breakin oil for 200 miles and then replace.

I also thought that when I replace the oil I could use a slik 50 lube to see how this works.

If all this doesn't work then I'll take the engine down and open cylinder 5.

Can anyone give me some feedback on this. Thanks!

Share this post

Link to post
Share on other sites

Unless the car is still misfiring, and if it has great power and drives great it seems very extreme to me to completely tear it down and replace the piston rings. If this is a race car/track car, perhaps it might be worth it, otherwise I still say drive it until it really needs new piston rings (assuming it is not misfiring)..

I think there are still some steps to take first, for example, using a borescope to inspect the cylinder walls for scoring or other problems.


Perhaps trying another new spark plug.

If it is still misfiring, has the variocam system been checked thoroughly?

I would stay away from slick 50 since I've read bad things about that, but certainly it might be worth a try using SAE 30 break in oil for 200 miles or so, and try out these procedures:


Edited by logray

Share this post

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this  

  • 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.