When it gets cold, does anyone suffer a drop in MPG? If not, what are the quick fixes for that and where on the engine are they located so I can change them out. Im averaging 24-27mpg on highway at 70 when I used to avg 30-32[est by usage of gas and miles traveled]. Also, would the cold weather have an effect on the engine since during cruise mode, normally the boost guage would sit between -7 and -5. Now it sits between -5 and -1/0.

It'* not so much the cold weather that does it, but the reformulated gas... Well, that'* only if you live in the snow belt (or colder climate areas). The reformulated gas tends to get lower mileage. All that winter additive crap...

The boost sits higher because the air is cold = more dense and has a lower moisture content. You should feel it in the 'butt dyno', but it shouldn't impact your mileage.

So its probably the reformulated gas causing a drop in MPG now that its winter?

Do they reformulate Gasoline for whinter?

I thought they only did that for Diesel?

Here'* an excellent read through:
Chevron - Fuel Economy

They do reformulate the gas in the winter time. I don't think that the above article says anything about it, but it does state other factors contributing to a decrease in mileage in the winter time.

what else on my car would help. A. where is the fuel filter at, and any special thign needed to change it[besides a clamp or two]. B O2 sensors, Location and method of changing. anythign else you can think of. I am having a oil change thie coming week, but thats every3k no matter, so I doubt its that.

You can see the front O2 sensor by the engine bay, its right on the downpipe, look like a plug, when you buy it, it come with the wiring, so you unplug the old one and remove it, that is screwed on the downpipe. Can be a little hard to remove since its on the exhaust.

No need to put lock-tite, they come already with something like lock-tite. Just retight the new one and plug the wire.

No need to reset the PCM.(if your PCM doesnt throw a code for a bad o2 sensor)

Lock-Tite... NO!!! anti-seize... YES!!!

DO NOT put lock-tite onto your O2 sensor!

The only sensor I would recommend putting back in if you need to replace them is a Genuine AC Delco sensor. No other sensor on the market can match the life of an AC Delco, plus the response of an AC Delco sensor is much better than any other over their life. Borg Warner sensors are absolute crap (one failed on me 400 miles (2 months) after installation on my Bravada and I only changed it as a preventative maintenance to pick up some lost mileage). And my experience with Bosch has been ok, but they have only lasted ~1 year in any GM vehicle I have installed them in. Don't go cheap on O2 sensors!

yes, sorry, thats what i was thinking and i said lock-tite...