XPost: rec.autos.tech, alt.home.repair   
   From: this@address.is.invalid   
      
   How could 50 to 100 clearings of the OBD codes (using a dumb OBD reader)   
   cause the catalytic I/M readiness monitor to set after months of not   
   setting?   
      
   Can the complicated electronics modules be "saving" scores of prior memory   
   sessions perhaps?   
      
   The storey is a bit confusing because the pieces only fell in together well   
   after the fact for each event, but here's the short summary of what   
   happened as I loosely recall the major happenstances of this purely   
   electronic ordeal.   
      
   [1] The check engine light has been on, on the dash, almost constantly   
   [2] Mostly when I looked, it would be P0420 bad cat pending & set codes   
   [3] I've been going through this regimen now, for about five or six years   
   [4] I didn't need smog for more than a year so I didn't worry about codes   
   [5] When it came within months of smog time, I cleared the OBD codes   
   [6] Mostly either the code comes back or the readiness monitor won't set   
   [7] But once in a while, the readiness monitor does set so I rush to smog   
   [8] I did that - it passed smog - but failed for a hose in bad condition   
   [9] I painted the hose black so that it would look like it's brand new   
   [10] But then for another month I couldn't get the readiness monitor to set   
   [11] At one point, I accidentally added gasoline with water (long story)   
   [12] The car ran like hell for an entire gas tank until I refilled it   
      
   After that, it passed smog and for months now, no codes.   
   What happened?   
   I have no clue.   
      
   A miracle?   
   A coincidence?   
      
   I do not know.   
      
   Maybe what "might" have happened is that during the time that I was driving   
   on the tank of watery gas, I had to keep the OBD code clearer on my lap.   
      
   Within a mile, the engine would stumble and I'd clear the codes and the   
   engine would run fine for another mile, and then it would stumble, and then   
   I'd clear the code and it would run fine for another mile, and so on.   
      
   This I did for at least a hundred, maybe two hundred maybe three hundred   
   times during the watery gas stage - but - miracles to happen I guess   
   because after that, no codes and, get this, the readiness monitors all set.   
      
   I passed at a different smog station (with the painted hose to make it look   
   like new not being an issue) and now I'm just wondering what the heck   
   happened?   
      
   Can it be that there is some kind of multiple instance "persistent memory"   
   inside one of the engine computers that I finally wiped out by clearing the   
   codes hundreds of times in a row?   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)