18 Oct 11 13:19, Mark Hofmann wrote to Roy Witt:   
      
      
      
    RW>> That's interesting. Why would that code fail the system? It has   
    RW>> nothing to do with emissions.   
      
    MH> In Maryland, the car will fail the emissions test if the CEL is on   
    MH> regardless of what the code is.  They also ensure the computer   
    MH> reports all tests passed (and none still in progress), which keeps   
    MH> you from being able to cheat by clearing the codes or resetting the   
    MH> computer by disconnecting the battery.   
      
   If you have a scanner that clears the codes, they can't tell if there was   
   a code in the computer. If you disconnect the battery, there's still a   
   history of the code in there, but no CEL. I have an HP Tuner, which can   
   clear codes as well as re-write most of the look-up stuff that's in there.   
      
    MH> I didn't realize the CEL light had anything to do with items other   
    MH> than emissions.   
      
   I think Mopars have two computers on board. At least the 90s models did.   
   Some of the higher end GM cars do as well.   
      
    MH>   When I read the code on the Durango and it said "power steering   
    MH> high pressure sensor", I was caught off guard.  I replaced it and the   
    MH> code went away, but had forgot to add more fluid at the time.  I   
    MH> didn't have any on hand and like many things, if you don't do it   
    MH> right away - you forget. It was about 2-3 inches low in the reservoir   
    MH> recently which was causing that noise.   
      
   I wonder if the human ear can hear that pump squealing sooner than the   
   sensor can detect low fluid?   
      
    MH> My daughter's car has an EGR low flow error when she first bought it.   
    MH> I found the problem to be a clog in the EGR port in the manifold   
    MH> (near the intake). The port was clogged with carbon and crud.   
      
   That's common on most cars. I had a Jap car with that problem. I had to   
   remove that EGR and clean it about twice a year. It was a low mileage car   
   to boot.   
      
    MH>   I have the software and cable needed to tell me when the car will   
    MH> pass with no issues after a reset of the system.  Once I saw the   
    MH> program report a green pass, I took it over right away to be tested.   
    MH> :)  It passed, of course.   
      
   I had a friend in San Diego who had a smog machine in his shop, even   
   though he wasn't a smog check station. He'd tune up oil burning cars to   
   just pass emissions at the state's inspection stations.   
      
      
                   R\%/itt   
      
      
     ... Only 5% of all humans have the privilege to live in America.   
      
   --- Twit(t) Filter v2.1 (C) 2000-10   
    * Origin: SATX Alamo Area Net * South * Texas, USA * (1:387/22)