Running Cold hurt MPG?

[tyrant609]

Like the title says. I just purchased a 95 3.4L and it runs much cooler than my last firebird. Im thinking previous owner might have pulled the thermostat. It takes it sweet time to inch its way a little above 160. Will running this cool hurt MPG?

Thanks

[Rob Bell]

Re: Running Cold hurt MPG?

Yes, because when the engine is cold, the PCM runs a richer mixture.

[tyrant609]

Re: Running Cold hurt MPG?

I figured. Guess im gonna go get a 180 degree thermostat and put it in there.

[ssms5411]

Re: Running Cold hurt MPG?

Depending on temp outside , it should take about 10 min. to hit 160 temp. Here in AZ it takes my car 5 mins. to hit 160 degrees, this is with a drilled 160 thermo and manual fan switch on.