FC 45

[Matt S Bower]

"David A. Cooley" wrote:
> 
> > Hey guys,  I could use some advice on this.  I have a 93 s10 blazer with
> > cpi.  It's setting a fualt 45.  Using the scan tool I am seeing that
> > when I cruize at highway speeds the O2 sensor voltage will hold at .85
> > volts and after a couple of minutes it will set the code and kick it out
> > of closed loop.  It then holds O2 volts at .92 and will stay usually
> > until I go back to start stop driving at which point the ecm goes back
> > to closed loop and the O2 sensor starts swinging from .1 to .8 volts.
> > Any ideas as to what I am not seeing here?
> 
> A couple ideas... Fuel pressure regulator could be stuck, Fuel return line
> could be plugged, or the PCM could have a problem.
> Was there anything that was done to the truck immediately before this
> started happenning? (Replace the O2 sensor maybe with a Bosch unit???)

Started out with code 44 and 45.  Started by changing O2 sensor and was
to a bosch unit.  code 44 went away but 45 comes back.

Thought of fuel pressure but keep forgetting to check it, somebody kick
me.

thanks