[ba] 5 cylinder now idles - but still not making the grade smog-wise

[Michael Heth]

On Sep 11, 2011, at 10:12 AM, Tony Lum wrote:

> Hi Micheal,
> 
> I feel for you because I had the same problem in my 87.5 coupe GT. 

Thanks for the detailed feedback about the issue.
> 
> One thing about cats.  There are 2 way and 3 way cats.  The 3 way cats have platinum in them to specifically reduce NOx.  The cheaper 2 way cats don't have this.

I think that is my issue as the cat I bought a while back (6-7 years) was only $150.

> 
>  This was back 4 years when the new dyno tests started.  Prior to that it always passed easily.

Yes that is what is tripping me up. Does okay at idle but is 10% over at 1500 RPM.

> 
> I believe that the California approved cats have the 3rd element in them and that's why they're way more expensive.  A 49 state cat is usually less than < $150, but CA approved cats will set you back more than $350.  BTW, its been 4 years since I changed to the Audi oem cat and it just passed smog easily 2 months ago.  There are aftermarket cats available that are CA approved and you may have to get one.  At least they should cost less now than they did back then.

Have found one for $260 or so, just going to make sure I can't get it local here for the same to help keep my $$ in the county.

> 
> Now normally, a $1400 part would send a '87 car straight to the scrap yard, but I paid only $950 for the car and I love driving it.  It pays me back by getting 25-26MPG and I can even get 32 MPG on straight freeway driving.

I have the same problems, car handles great, is now a classic and gets 20 around town and about 28 on the freeway. A new car that gets the same mileage (that I would enjoy driving) is around $30K.


M./

Michael Heth
classic_coupe at serversmiths.com