ECM fault?

[Ludis Langens]

Geoff Richards wrote:
> 
> Mike wrote
> 
> > How do you figure???  Did you erase the ecm... make it go dumb? Then drive
> > it for a while?.. the o2 sensor is not used when you first start up or
> when
> > you are idling correct?
> I beleive the 02 sensor is not used at idle as there is a richer idle map ?
> for idle
> quality (smooth)

Some ECMs (many? all?) _do_ use the O2 sensor at idle.  For example, the
2.8 MPFI as used in the Fiero.

On the other hand, my carbed EEC IV Ford 2.8 needs to be rich at idle. 
Air injection is used to clean up the exhaust.  Trying to set the carb
to stoich at idle wasn't pretty.

-- 
Ludis Langens                               ludis (at) cruzers (dot) com
Mac, Fiero, & engine controller goodies:  http://www.cruzers.com/~ludis/