I've also been told an oil change helps. Don't know how though. 

Sent from my iPhone

> On Sep 22, 2017, at 3:47 PM, Steven Johnson <sjohnso2000@GMAIL.COM> wrote:
> 
> You definitely want to get the engine good and warm so that the catalytic
> converter is well heated
> so that it is doing the best job it can for a smog test.  Driving just down
> the street will not warm it
> up enough.   You need to drive it for 15 minutes to 1/2 hour, especially
> with the cooler temps in
> your area.   If you have not done a tune-up in a while, I'd be sure to do
> that as well.
> 
> Steven
> 91 Westy
> 
>> On Fri, Sep 22, 2017 at 2:46 PM, David Boan <dboan@outlook.com> wrote:
>> 
>> I recently moved to Idaho and had to get an emissions test for my '85
>> Westy, which I did today.  It failed one part of the test - the HC (PPM) at
>> idle were 350 (the standard is 220).
>> 
>> 
>> I spoke with my mechanic who said it was possible that the catalytic
>> converter was not warmed up enough (I had only driven the van down the
>> street a few miles before the test).  He suggested driving for awhile and
>> test again.
>> 
>> 
>> Has anyone run into this?  Does that advice sound right?
>> 
>> 
>> Thanks
>> 
>> David
>> 
>> Boise ID
>> 

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