> jakdedert wrote:

>> Last Friday I took my trusty Corolla in for the annual smog check. It
>> failed. Max allowable HC level was 220 ppm. Mine read 225...something
>> like 2%% high. Frankly, I've not changed the plugs in the beast since
>> sometime early in this century, some 50k miles ago. Did that immediately
>> and noticed a slight, barely perceptible increase in performance. Also
>> checked the air filter, which has probably not been changed since the
>> 20th century; but is checked and cleaned occasionally. It looked fine,
>> although I knocked some dust out of it.
>>
>> No problem, I think. It probably will pass, since it was such a small
>> overage, and the plugs were really worn...EXCEPT; this one's so old that
>> they have to check with a probe up the tailpipe (Ouch! Something about
>> writing that made me feel distinctly uncomfortable)--no ECU terminal
>> hookup. No other instrumentation is connected to the car. That's fine.
>> They've been doing this every year for the the last 15 that I've owned
>> this particular vehicle...EXCEPT; this time--before failing the car--they
>> asked me to run the engine up to 2350 RPM and hold it. Okay...EXCEPT;
>> there's no tachometer on the car! They'd always checked it at idle
>> before.
>>
>> The woman coached me to 'press a little harder, more, more...okay. Right
>> there! Now hold it.', which I did for about 30 seconds. Then she handed
>> me the rejection.
>>
>> Does anybody think that a barely-trained, probably minimum wage worker
>> can judge a strange vehicles engine speed, *by ear*, to the degree of
>> precision necessary for this test? Anyone have an idea what would be the
>> effect of too low, or too high, an engine speed on the results?
>>
>> This seems like high-tech witchcraft to me. If the state is going to
>> deny me registration based on someone's 'trained' ear....
>>
>> jak

>
>
> Okay, did a little research. No idea why she told me to hold 2350 RPM.
> The test standards mandate an idle test, followed by a second phase
> (presumably on failing the first one), AFTER an '...engine conditioning
> phase consisting of engine operation at approximately 2500 RPM for
> approximately 20 seconds.' Problem is, she pulled the sheet immediately
> after I dropped the speed back down to idle...no time for a second
> test...but no need for absolute precision during the 'engine conditioning
> phase'. It's probably just to blow out any carbon accumulated from the
> nearly one hour of idling in line.
>
> I think this is nothing. She'll probably pass with flying colors this
> time out. Always has before...runs like a top. Still a PITA.
>
> jak