Most likely a simple adjustment of the mixture screw will cure this.
You need to find someone with a three gas analyzer who will do this for
a reasonable price.  I usually use the guys in the vans parked next to
the emission test stations here in Washington and pay $20 or so.

Antaki wrote:
>
> I have also heard of the cylinder wall cracking if run too long w/o coolant.
> After all, they are just thin sleeves. This causes pressurization of the
> cooling system in the same manner as does the leaking head seal problem.
>
> Now the question - my '88 fails smog check (CA)with too high HC at idle, but
> does fine at 2500 RPM. But it also will rev up to 2000 RPM or higher on it's
> own, usually when warm. Blipping the gas does not cure it. I believe the two
> are related.
>
> The accelerator cable is not sticking, the O2 sensor is fairly fresh, I
> opened and looked into the airflow meter, and it looks ok, and measures
> within specs, resistively speaking. I believe the temp sensor (left front of
> engine) is ok. I've checked all the grounds and electrical connections I can
> find, and am considering doing brain surgery to it next.
>
> Ideas?
>
> Thanks,
>
> Ron Antaki

--
Stuart MacMillan
Manager, Case Program
800-909-8244 ext 208

Getting your share of the Net yet?
http://www.cobaltgroup.com
http://www.casedealer.com/demo
http://www.caseihdealer.com/demo