Fuel & air mixture screw - Mercedes-Benz Forum

Go Back   Mercedes-Benz Forum > Mercedes-Benz Sedan Forums > W201 190 Class
New User? Register - Forgot Password

BenzWorld.org is the premier Mercedes-Benz Forum on the internet. Registered Users do not see the above ads.
Reply
 
LinkBack Thread Tools Display Modes
Old 06-21-2012, 04:44 AM   #1 (permalink)
BenzWorld Member
 
Date registered: Sep 2009
Vehicle: 86 190e 2.3 8v with 120K
Location: New Jersey
Posts: 113
Fuel & air mixture screw

I had some work done at a shop and they said they played with the mixture screw on the throttle body. I can hardly sit at a light now without the car stalling. Where should the screw be so I can correct the problem instead of bringing it back to these idiots.
Squills is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 06-21-2012, 07:42 AM   #2 (permalink)
BenzWorld Elite
 
Nfsjunkie91's Avatar
 
Date registered: Aug 2010
Vehicle: '87 190E 2.3
Location: Western Maryland, USA
Posts: 1,703
Quote:
Originally Posted by Squills View Post
I had some work done at a shop and they said they played with the mixture screw on the throttle body. I can hardly sit at a light now without the car stalling. Where should the screw be so I can correct the problem instead of bringing it back to these idiots.
Take your air cleaner off, it's located here on the fuel distributor.


Provided your injection system is still functioning correctly, you should get a multi-meter with a duty cycle and then adjust according to this procedure: http://www.startekinfo.com/StarTek/o.../PDF/30006.pdf Job 7.3-105, subsection a. Browse the forums to find which pins on the diagnostic port you need to connect to.
__________________
W201 Euro + NAM Headlight Diagram. --- Detailed OVP Information. Click only on OVP_Info.pdf. --- W201 Differential Ratios
--- Mercedes Timing Chain Crimper (Single/Double Row) Tool for Rent. PM me for details. ---
1982 W123 300D Turbodiesel for sale whole or as parts, W126 Euro parts for sale (SEC hood, bumper, lights, etc), PM me.
Nfsjunkie91 is online now   Reply With Quote
Old 06-21-2012, 11:21 AM   #3 (permalink)
BenzWorld Elite
 
Date registered: Dec 2008
Vehicle: 1993 190E 2.6, 1990 300SEL, 1992 300SE, 1992 400E, 1987 190E 2.6 murdered by my brother.
Location: San Franciscisco, CA & Las Vegas, NV
Posts: 1,291
Aww man...its a nightmare once they messed with the air fuel mixture. I have a factory sticker on my car that says it is preset at factory and do not adjust. You have to know what you are doing....and plug the volt meter set on duty cycle in that round circle with the cap by the ABS module. I would not go back to those guys anymore. Mechanics cheat by adjusting that screw instead of diagnosing and fixing the real problem. Make them pay for it....and take it to someone that knows 201s if you cannot do it.
__________________
There is one rule...there are no rules!
Runninrebel211 is offline   Reply With Quote
Old 06-23-2012, 09:43 AM   #4 (permalink)
BenzWorld Member
 
Date registered: Feb 2009
Vehicle: 98 SLK230K AMG, 98 E55T, 89 2.5-16
Posts: 213
yeah that mixture screw is always the fall guy when the mechanic can't find the real culprit
raymondgallant is offline   Reply With Quote
Old 06-23-2012, 10:07 AM   #5 (permalink)
BenzWorld Elite
 
slk230red's Avatar
 
Date registered: Mar 2004
Vehicle: '01 SLK230,'93 190E 2.3, 1971 LS5 Corvette Convertible
Location: Tampa, FL
Posts: 1,872
Quote:
Originally Posted by Squills View Post
I had some work done at a shop and they said they played with the mixture screw on the throttle body. I can hardly sit at a light now without the car stalling. Where should the screw be so I can correct the problem instead of bringing it back to these idiots.
What work was done to your car? Yes, adjusting the mixture screw is just compensating for other issues, especially vacuum leaks. When the 2.3 is running right, you make them stall.
slk230red is offline   Reply With Quote
Old 06-23-2012, 09:16 PM   #6 (permalink)
BenzWorld Member
 
Date registered: Sep 2009
Vehicle: 86 190e 2.3 8v with 120K
Location: New Jersey
Posts: 113
I had the oxygen sensor replaced because i couldnt seem to get the stupid thing out. I also asked for them to check for vacuum leaks cause I could tell the car was not running right. Well after saying that they couldnt find any leaks I got a call the next day saying oh we think we found one at the throttle body and we played with the mixture to try and get it running better. Well it hardly ran. After reading up on how to adjust it I think I have it back to normal and checking the duty cycle I have it back to 70% which seems to be the normal.
Still not running well enough to drive but I know I will never bring the car back there!
Squills is offline   Reply With Quote
Old 06-24-2012, 07:58 AM   #7 (permalink)
BenzWorld Elite
 
slk230red's Avatar
 
Date registered: Mar 2004
Vehicle: '01 SLK230,'93 190E 2.3, 1971 LS5 Corvette Convertible
Location: Tampa, FL
Posts: 1,872
The first thing I would do is check the vacuum hoses going to and from the Idle Control Valve. You want good soft hoses with tight connections.
slk230red is offline   Reply With Quote
Old 06-24-2012, 08:15 AM   #8 (permalink)
BenzWorld Junior Member
 
Gabodude's Avatar
 
Date registered: May 2012
Vehicle: Mercedes-Benz 190e 2.6
Location: Dieppe, NB, Canada
Posts: 30
Quick thread jack... Where is the Idle control valve on the 2.6? ...thread jack over.
Gabodude is offline   Reply With Quote
Old 06-24-2012, 08:23 AM   #9 (permalink)
BenzWorld Elite
 
slk230red's Avatar
 
Date registered: Mar 2004
Vehicle: '01 SLK230,'93 190E 2.3, 1971 LS5 Corvette Convertible
Location: Tampa, FL
Posts: 1,872
Quote:
Originally Posted by Gabodude View Post
Quick thread jack... Where is the Idle control valve on the 2.6? ...thread jack over.
In front of the Fuel Distributor with a 2 wire connector plugged in to it.
Attached Thumbnails
Fuel & air mixture screw-2.6-fuel-lines.jpg  
slk230red is offline   Reply With Quote
Old 06-24-2012, 08:50 PM   #10 (permalink)
BenzWorld Junior Member
 
Gabodude's Avatar
 
Date registered: May 2012
Vehicle: Mercedes-Benz 190e 2.6
Location: Dieppe, NB, Canada
Posts: 30
Quote:
Originally Posted by slk230red View Post
In front of the Fuel Distributor with a 2 wire connector plugged in to it.
Thank you, sir!
Gabodude is offline   Reply With Quote
Reply

  Mercedes-Benz Forum > Mercedes-Benz Sedan Forums > W201 190 Class

Bookmarks



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -7. The time now is 03:40 AM.



Powered by vBulletin® Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO 3.6.1

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.