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Subject:Re: Running rich and low mpg
From:John Lauterbach
Date:Fri, 22 Mar 2019 13:18:45 -0400

As others have posted on this list previously, disconnect the O2 sensor when van
is cold.  Put a good voltmeter on the leads and watch what happens.  Remember
something about voltage when van is warm hangs around 0.5 volt.  john
On Fri, 2019-03-22 at 09:46 -0700, Dan Lamb wrote:
> Sounds like what happens when O2 sensor fails. Ecu never sees the sensor warm
> up so leaves mixture rich and mpg goes down. They can be tested. May also need
> to check connection for deterioration.
> Sent from my iPhone
> > On Mar 22, 2019, at 9:36 AM, Dan N <dn92610@gmail.com> wrote:
> > hi all,
> > 1990 tintop 2.1 WBX seems running rich and low mpg. Fresh tune up -
> > sparkplugs, dist. cap and rotor, new Temp2 sensor, vacuum lines
> > checked,throttle body clicking right, fresh air filter and fuel filter, new
> > coil,swapped in a known good used AFM but still running rich... running good
> > nohesitation or stumbling, good idle @ 900 rpm, coolant gauge needle
> > justunder the red dot.
> > so the questions are:
> > - is there a problem with the injectors? should I get new ones?- is there
> > adjustment somewhere to do? ie. adjusting the AFM?
> > thanks in advance
> > dan