I _think_ a lean-running engine will result in excess NOX.   If it's
running too rich, I think you get excess HC.  Were the HC readings
really low?  I'm a novice here, so keep that in mind.  Maybe the
timing is not set properly?  Is it set to 5 degrees before TDC?
Sometimes these vans are setup to run 5 degrees ATDC, which some
people say improves performance, but I think results in higher
emissions.  (I'm kind of guessing here.)

You can also try putting a new cat on the exhaust and running the van
on the freeway for 20 minutes prior to the emissions, leaving it
idling to keep it hot until the last minute prior to getting it
tested.

-- Craig

On Wed, 25 Aug 2004 11:11:01 -0400, Melvin Mudgett-Price
<mprice@acmex.com> wrote:
> Took my van for its Ohio e-Check yesterday. The engine has 20,000 on a
> rebuilt Boston Bob. It passed with flying colors 2 years ago. This time
> it failed on Nitrous Oxide emissions, they are supposed to be around
> 900, mine were 1,900.
>
> I called my regular mechanic (VW specialist) and he said there was
> nothing he could do, when van's start failing their emissions test
> that's usually the end for them. This sounds like total bs to me and I
> don't know why he doesn't seem to want to even look at the van. Called
> another VW shop and they said no problem, bring it in.
>
> Now to my question. What sort of things would cause the "NO" to be high.
> I would like have some idea not because the mechanic will try bamboozle
> me but because I don't like to be in the position where he could.
>
> Thanks
> Melvin
> 83.5 Westy
>