Worries about P&G not lighting the cat

Discussion in 'Emissions' started by SentraSE-R, Jan 14, 2010.

  1. SentraSE-R

    SentraSE-R Pishtaco

    I've been hypermiling for over a year with my SE-R, and it needed to pass a smog check this year. I was worried that P&G might keep the catalytic converter too cool to handle emissions, or (worse) might contaminate the cat.

    So before I took my car in for the smog test, I took if for a 20 mile drive to warm it up. Force of habit, and my never-ending quest for FE had me P&G my way to the halfway point. Then I drove it back on the freeway at 55 mph to light the cat for 10 miles.

    Unfortunately, I got to the smog check station, and another car was in the bay being smog checked. My car and its cat sat cooling for the next 15 minutes.

    To make a long story short, my car passed with normal results.
  2. echoman

    echoman Well-Known Member

    Nice story. I cant believe you hypermile a SE-R lol.

    Here in Ontario, we call the test, drive clean test. I am a certified tester, not a repair tech. Most cars will pass these days but there are still some that need to be repaired. Usually with toyotas its O2 sensors. Not to often have we changed a cat.

    We are supposed to run the car on the dyno untill we start the test to make sure the engine is warmed up and ready. So maybe they did the same. I tested my own car last year and didnt run it on the dyno (didnt want to waste the gas hehe). It warmed up in the pre-test, like all models and passed with flying colours. Good to hear your car is tip top shape, even with all the hypermiling and P&Ging you do.
  3. xcel

    xcel PZEV, there's nothing like it :) Staff Member

    Hi Darrell:

    ___If your coolant temp is up to standard operating temperature (185 to 200 or whatever the SE-R is good for), your CAT is lit.

    ___Good Luck

  4. Yaris Hilton

    Yaris Hilton Half a Bubble Off Plumb

    I don't believe that's necessarily true. The cat will cool off a lot faster than the engine will. I know that if I drive my warmed up Yaris home, switch it off and run into the house, run back out, jump in, start up and back out of the driveway, I can smell unburned alcohol fumes (E10 gas) as the cat's died in that moment I'm in the house, with the engine still warm. I'm sure it quickly relights as I drive away. It'd take testing to know what engine-off interval will let the cat go out in a given vehicle. The O2 sensors will also cool quickly with the engine switched off. They're reheated electrically.
  5. oilburner

    oilburner Active Member

    Considering o2 sensors need around 600 degrees farenheit to operate, I'm sure they cool off to below that point fairly quickly. Actually most sensor heaters run continuously to make sure they are always reading properly.
  6. The Doctor

    The Doctor Old Dude, New Car

    Being still pretty new to this forum, I'm amazed at the number of abbreviations used that I'm unfamiliar with. I got past "lighting the cat" but was brought up short at "P&G".


    When four or five abbreviations hit in the same sentence, it can get pretty confusing for the newcomer.

    Do y'all have a glossary of terms somewhere? :rolleyes::confused::D:D

    Doc :cool:

    Oooops! I found the Glossary in the left hand tool bar, but there doesn't seem to have anything in it. ???
  7. PaleMelanesian

    PaleMelanesian Beat the System Staff Member

Share This Page