Frankly, I doubt that you need a new AFM if the van runs well otherwise,
but since you have it at the dealer have him substitute a new one from
HIS parts department and see if he can get it to meet specs.  I would
not let him put one on, find it doesn't fix it, and then keep replacing
parts until he finds the real problem, making you pay for all the parts
that didn't need replacing.

If it does pass, get a rebuilt unit from BD for $125.

If it doesn't, find out which is bad, HC or CO. The Cat and AFM
adjustment will affect the CO.  HC elevation is usually from misfiring
or an over rich condition.  Misfiring is usually an ignition system
problem (or a bad injector, less likely).  If the ignition system
components are okay, then you have a fuel injection problem.

I had a difficult time with mine this time around, and finally passed
when I asked the tester to not use the funnel extension on the tail
pipe.  The rules specify the probe must go in 10", and some sticklers
use the extension, which concentrates the gasses and can cause a
marginal vehicle to fail that would pass without it.

Good luck!
--
Stuart MacMillan
Manager, Case Program
800-909-8244 ext. 8208
Fax: 206-269-6360

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