XPost: alt.home.repair, ca.driving   
   From: kludge@panix.com   
      
   Arlen   Holder   wrote:   
   >On 17 Nov 2020 23:57:22 -0000, Scott Dorsey wrote:   
   >   
   >> Okay.  You're getting an error which is saying that the ratio between the   
   >> forward O2 sensor and the rear O2 sensor is not what it should be.   
   >   
   >I appreciate your advice as I'm not quite sure what readings to look at.   
   >o Let me know what information you need to help me figure out what to do.   
      
   Read the message over again.  What you want to know is in the graphs for the   
   two O2 sensors and how they track.   
      
   Don't worry so much about the ratio itself, worry about how they track.   
      
   But you will not figure the problem out just by looking at the plots, you will   
   figure the problem out by thinking about how the emission control system works.   
      
   >When do I take the readings once the engine is warmed up?   
      
   All the time.  You take them before it warms up, you take them after it warms   
   up, you take them over the course of driving around.  What you are looking for   
   is trends and correlation more than specific values.   
      
   >>  The shape of the time-domain curves   
   >> will be different from one model to another, but just watch.  The second O2   
   >> sensor might be bad... the converter might be bad..... and it's -possible-   
   >> that the converter is just overwhelmed with junk (although that it is least   
   >> likely of the three since you aren't seeing any other errors).  But watch   
   >> the numbers.   
   >> And you want to look at it for as long as you can... because you can have a   
   >> loose O2 sensor cable, or a bad engine ground, and see weird spikes on those   
   >> graphs that occur very very seldom but which can lead the computer to set   
   >> an error.   
   >   
   >I don't have the necessary equipment to save or see graphs.   
   >o I can only see the live data as it happens.   
      
   Well, that's useless.  So you're going to have to plot it on semilog paper   
   by hand.  Your scanner does not provide ANY plotting functions?   
   --scott   
   --   
   "C'est un Nagra. C'est suisse, et tres, tres precis."   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)