What temp' does Motronic go to closed-loop?

Brad Anesi banesi at novell.com
Sun Jan 19 01:54:37 GMT 1997


Greetings from the North Pole...

With the ice-cold weather we've had here in the northeast, my Alfa 164's
coolant temperature doesn't get any hotter than about 135 degrees F'. 
Along with that, I've noticed a drop in gas mileage by about 20%.  While I
expect some drop in efficiency due to longer warm-up times, I'm
wondering if the Motronic is even going to closed-loop.  Alternatively, if it
is going closed-loop, maybe it's being kept somewhat richer due to the
lower coolant temperature, resulting in the decreased gas mileage.

For those of you on the EFI-Digest, the '91 Alfa uses a Motronic 4.1 with
a 3-wire O2 sensor.  While I'm sure the mappings are different from car
to car, I suspect the temperature change-points are similar on
(water-cooled) Motronic-equipped cars, yes? 

Any thoughts on the matter?

Thanks,

Brad
'86 Porsche 911 Coupe (in hibernation for the Winter)
'91 Alfa 164       




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