XPost: sci.electronics.repair, alt.home.repair   
   From: bobnospam@gmail.com   
      
   On 4/23/2023 7:51 AM, mike wrote:   
   > 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?   
      
   Or, did the water clean up the catalyst?   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)