Home  |  Forums  |  914 Info  |  Blogs
 
914World.com - The fastest growing online 914 community!
 
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG. This site is not affiliated with Porsche in any way.
Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners.
 

Welcome Guest ( Log In | Register )

> Some advice please, High Emissions CO
DavidSweden
post Jul 8 2021, 04:02 AM
Post #1


Member
**

Group: Members
Posts: 479
Joined: 8-June 14
From: Sweden
Member No.: 17,452
Region Association: Scandinavia



This morning I took the car for the government road worthy test and it failed due to high CO emissions . (IMG:style_emoticons/default/headbang.gif)

The CO value measured at the tail pipe was 6,2% it need to be under 4,5% (not sure what the units are something they call CO/K value)

If members have any advice on how to reduce the CO it would be appreciated, I have to fix it by the 9th of August otherwise I cant drive the car (IMG:style_emoticons/default/headbang.gif) (IMG:style_emoticons/default/headbang.gif)

The engine is a 2l with 20556 PC´s and running D Jet

Thanks in advance
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
 
Reply to this topicStart new topic
Replies(1 - 6)
JOEPROPER
post Jul 8 2021, 07:26 AM
Post #2


The answer is "no" unless you ask...
***

Group: Members
Posts: 1,191
Joined: 21-November 15
From: White Plains New York
Member No.: 19,387
Region Association: North East States



Start with the basics. Ignition timing, vacuum leaks, visual inspection etc... High CO is a result of rich running condition. (too much fuel / not enough air). Could be caused by a few things, some of which may require diagnostic equipment. (DVOM, gas analyzer, Air fuel ratio sensor) May be something simple like clogged air filter, or 1-2 clicks on the control unit. After inspecting the basics, I would start with the DVOM and test cyl head temp sensor, TP sensor and fuel pressure. These are easy places to begin with. I'm sure you will get some good advice here.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
barefoot
post Jul 8 2021, 07:39 AM
Post #3


Senior Member
***

Group: Members
Posts: 1,334
Joined: 19-March 13
From: Charleston SC
Member No.: 15,673
Region Association: South East States



If all else fails, turn down the fuel pressure several PSI, will lean out the mixture for the test. Easy to do.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
ddire333
post Jul 8 2021, 08:48 AM
Post #4


Member
**

Group: Members
Posts: 91
Joined: 2-November 20
From: ireland
Member No.: 24,835
Region Association: Europe



Get one of these, or the newer version - I check and adjust idle mix before the road worthiness test, you see the impact of any changes you make right way.

your not so far off so change @ ecu or pressure should do it


https://www.ebay.ie/itm/114874653710?hash=i...zEAAOSwpHZg3fRb
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
JamesM
post Jul 8 2021, 10:05 AM
Post #5


Advanced Member
****

Group: Members
Posts: 2,023
Joined: 6-April 06
From: Kearns, UT
Member No.: 5,834
Region Association: Intermountain Region



As has been mentioned, could be slightly rich, or at least reflective of not burning a all the gas properly though it is also worth noting I have had similar emissions failures just from having older gas in the tank when running the test.

What RPM was the test run at?


I would
1. Make sure you have a fresh tank of gas and your air filter is clean
2. Make sure your engine is as warm as you can get it before testing (if the head temp sensor isnt fully hot it will richen your mixture during the test)

If its still failing by that small ammount:
3. a. If the CO reading is failing at idle, dial the idle mixture knob to the left until 1 click before you start getting a lean idle hunt
b. if the CO reading is failing at speed, dial the fuel pressure down a bit.

There is a possibility you could have an issue with your MPS, but i would start with the above.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
dr914@autoatlanta.com
post Jul 8 2021, 10:26 AM
Post #6


914 Guru
*****

Group: Members
Posts: 8,110
Joined: 3-January 07
From: atlanta georgia
Member No.: 7,418
Region Association: None



6.2 is outrageous should be 2 % Immediately check the manifold air pressure sensor to see if it holds vacuum. If not that is the problem. Colorado less dense air at the higher elevations automatically means a richer air to fuel mixture


QUOTE(DavidSweden @ Jul 8 2021, 03:02 AM) *

This morning I took the car for the government road worthy test and it failed due to high CO emissions . (IMG:style_emoticons/default/headbang.gif)

The CO value measured at the tail pipe was 6,2% it need to be under 4,5% (not sure what the units are something they call CO/K value)

If members have any advice on how to reduce the CO it would be appreciated, I have to fix it by the 9th of August otherwise I cant drive the car (IMG:style_emoticons/default/headbang.gif) (IMG:style_emoticons/default/headbang.gif)

The engine is a 2l with 20556 PC´s and running D Jet

Thanks in advance

User is offlineProfile CardPM
Go to the top of the page
+Quote Post
wonkipop
post Jul 8 2021, 07:17 PM
Post #7


Advanced Member
****

Group: Members
Posts: 4,670
Joined: 6-May 20
From: north antarctica
Member No.: 24,231
Region Association: NineFourteenerVille



do you have a factory manual?
good for step by step check.
you need access to an exhaust gas analyser.

tips about car being fully warmed up at at operating temp before test good advice.

good luck, bright side is emission test picked up car running rich.


Attached Image
User is offlineProfile CardPM
Go to the top of the page
+Quote Post

Reply to this topicStart new topic
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:

 



- Lo-Fi Version Time is now: 26th December 2024 - 08:16 PM