Jump to content

Server Lease Renewal/Software Licenses

Our yearly server lease, software licenses, as well as hardware operating costs, ARE due Dec 6th, 2021. Our current donations have fallen far short of the funds we need to renew. Please remember the RennTech.org community is Member supported so please consider a donation to help...  THANK YOU!

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)

Help with diagnosis?


Recommended Posts

Hello, I have a 1999 996 C2 6-speed with 91,000 miles. Only mods are a K&N filter, headers, and an old K-40 radar detector hard-wired into the DME. I bought the car about a month ago for a steal at $9,000.00 because the engine light was on and it had a rough idle. I was hoping for some help with diagnosing its problem(s).

Symptoms:

1. rough idle - rumbles like a muscle car and sometimes idles is at 700rpm and sometimes at 1200rpm.

2. Difficulty starting about 1 in 5 times. Requires excessive turn over and priming with more gas.

3. Poor mileage - 12-13 mpg

4. Sometimes smells like it is running rich

5. Gas tank won't fill to Full; it never shows above 7/8 tank.

6. Check engine light is on most of the time, but occasionally goes off for a day. Usually goes on when I'm in higher rpm's.

7. Very tiny intermittent oil leak coming from passenger side front of engine bay.

Codes:

1. P1539 - Camshaft adjustment bank 2 (4-6) Frequency 166

2. P0446 shutoff Valve Activate Charcoal Filter; Frequency 2

3. P1124 Oxygen sensing range 1 Cyl 1-3

4. P0455 Tank Ventilation (Major Leak)

My thoughts so far:

1. Air oil separator causing vacuum leak, causing it to think it's running lean, and then overcompensating by enriching the mixture, hence the P1124, rough idle, problems starting, and intermittent oil leak.

2. Camshaft problem - I'm not sure there's a problem with the camshaft actuator itself because I great great performance from the car in all rpm ranges; it pulls great above 3k rpm so you'd think performance would be affected if it were unable to adjust. That leaves either a bad sensor, a problem with the DME from the K40 radar detector, or something in between.

3. Fuel tank may be a purge valve issue, blocked vent tube, or the fact that the k40 intentionally causes the gas cap light to turn on when it detects radar and this in turn caused the error. The K40 cause still wouldn't explain the inability to read "Full" on the gas gage.

I'd appreciate any input and/or differing opinions!

post-66625-0-82842400-1298235241_thumb.j

Edited by pkhoffman
Link to comment
Share on other sites

Thanks for the reply, Loren! Excellent point about the AOS. Where would you recommend I start looking with the P0446 and P0455's?

No P1126?

How could the AOS only affect one engine bank?

I would start with the P0446 and P0455 - you've got a leak that needs to be addressed.

Fix that problem - clear the codes and see what comes back. I thing at a time as they say...

Link to comment
Share on other sites

  • Admin

P0446 EVAP Canister Shutoff Valve (Function) - Below Lower Limit

Possible causes:

- Purge air line blocked.

- Flow resistance of EVAP canister too high.

Most of the time this problem is the purge valve.

P0455 Fuel Tank Ventilation System (Major Leak) - Below Lower Limit

Possible causes:

- Tank cap missing.

- Ventilation lines detached from EVAP canister.

- Ventilation line detached from tank.

- Ventilation lines detached from operating vent valve.

- Ventilation line detached from fuel tank vent valve.

- Break in ventilation lines.

Start by inspecting the cap for cracks and the o-ring on the cap.

If all looks well there then remove the right front wheel and start infecting the canister and the lines for road damage.

  • Upvote 1
Link to comment
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.

Guest
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.

×
×
  • 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.