If one makes the presumption that your reading is a bit less than .5 to .8 volts when driving, and that your O2 sensor along with temp 2 sensor are good, it would indicate a lean mixture. This would have me looking for exhaust leaks ahead of the O2 sensor, or even intake leak after AFM. 

Why? Your MPG is down. An exhaust leak introduces oxygen into the exhaust giving false lean readings and the ECU tries to compensate by dumping in more fuel.  An intake leak introduces unmetered air having a similar effect. 

Chris.

Wysłane z iPhone'a

Dnia Jan 2, 2012 o godz. 14:34 B Feddish <uprightbassghost@HOTMAIL.COM> napisał(a):

> I’ve got that issue where the van runs fine cold then gets sluggish when warm.  Mileage is down to 15 in the city too.  When I disconnect the O2 sensor it runs better warm.  I connected the volt meter and while disconnected it ranged from 0V at cold to about 1 volt after a few minutes it pretty much stayed there.  Then I connected it back up and left the volt meter on. It went up and down from .15 to .17 at about 2000 RPMs and stayed in that range.
> 
> Thoughts....
> 
> Thanks,
> Bryan