Mercedes SLK World banner

Status
Not open for further replies.
1 - 15 of 15 Posts

·
Registered
Joined
·
23 Posts
Discussion Starter #1
My oxygen sensor on my 98 slk 230 is bad so i try to figure out the location but couldn't find the sensor! Your help would be greatly appreciated... :)
 

·
Administrator 2009 SLK 55 AMG/Founding Member 2006
Joined
·
97,308 Posts

·
Administrator 2009 SLK 55 AMG/Founding Member 2006
Joined
·
97,308 Posts
why not? it says 1 sensor and the location before the cat
 

·
Administrator 2009 SLK 55 AMG/Founding Member 2006
Joined
·
97,308 Posts

·
Administrator 2009 SLK 55 AMG/Founding Member 2006
Joined
·
97,308 Posts
see above post for parts diagram link
 

·
Premium Member 2013 SLK250
Joined
·
2,415 Posts
From the top of the engine look down on the left side between engine and battery about a foot down on the exhaust pipe is the first one. There is a second one after the cat.
 

·
Registered
Joined
·
130 Posts
They are always located on the exhaust system, screwed into a bung, perpendicular to exhaust flow. Since the advent of OBDII ca. 1996, all cars have had at least two sensors. There will always be one before entry to a catalytic converter and one after. If the engine has two banks such as a V8 or V6, it has sensors before and after both cats.

The system measures the difference in exhaust temperature before and after the catalytic converter. If it does not see at least 100 degrees Fahrenheit Delta, it considers the catalytic converter not working properly and sets a code.
 

·
Registered
Joined
·
23 Posts
Discussion Starter #10
I can located one of the sensor from top of the engine but still have to jack the car up for easy access, I might have to do it this weekend.. I will post picture up for anyone interest :)
 

·
Premium Member
Joined
·
166 Posts
1998 230slk have only one Oxygen sensor and it is located on the engine (exhaust pipe) prior to the Cat Converter and its exhaust portion of the exhaust system. Accessible on the Right hand drives from the engine bay or from underneath the vehicle then as per jbanks15 posts.
 

·
Per ardua ad cineris.
Joined
·
1,039 Posts
The system measures the difference in exhaust temperature before and after the catalytic converter. If it does not see at least 100 degrees Fahrenheit Delta, it considers the catalytic converter not working properly and sets a code.
Aligned with this information, the Lambda sensor measures the remaining level of oxygen in the exhaust flow. (Partial Pressure of Oxygen, aka ppO2)
So the current crop of oxygen (lambda) sensors are self-heated, and accurate at low ppO2 levels, but tend to have quite a slow response time (10s of seconds).
And I suppose the indication of optimal fuelling is when there is almost no oxygen before the catalyst, and the same amount in the sensor after the catalyst. Too much fuel, and there's no oxygen left, and too little fuel and the nitrous oxides are generated, but the ppO2 will be too high.

So a fine tuning input for the fuelling which is already tuned by the MAF, and primarily controlled by the revs/throttle setting.
How subtle is this control due to be?
 

·
Registered
Joined
·
23 Posts
Discussion Starter #13
Ok so I got a chance to change all two o2 sensor but the engine light still on the code is p0133. The code reader said O2 Sensor Circuit Slow Response (Bank 1 Sensor 1) anyone got any idea?
 
1 - 15 of 15 Posts
Status
Not open for further replies.
Top