I had my oil change, transmission fluid change, new air filter and fuel filter done after 33k miles and watched my MPG climb, climb and climb.
When I first got the car I could only get up to 31.1mpg average max.
After that it dropped to around 29 for a long time.
The little 2.2 got up to 32.8 mpg, then I filled up with some Circle K gas in an emergency and it shot down.
I refilled with Shell 87 once again, and it climbed back to 32mpg, but is lingering there and does not seem to want to climb and climb like it did.
If they did not go to the winter fuel mix, I know my average would have at least been 33mpg.
I had the wife's Ecotec 2.2 Sunfire on CC at 70mph driving to Vegas and it landed a little over 37mpg. Usually she got 29mpg, and I know it is because she needs new O2 sensors. She has 110k miles on the original sensors. I am hoping this pay I can afford to have new ones installed. I know the MPG with all the mods she has will go up to at least 35mpg average and 39mpg all freeway. If I get the 4:2:1 header and downpipe installed, it will go up even more. I am going off of all the others here and on the J forum about their jump in fuel efficiency after header install. Some claimed a 5mpg jump, I am skeptical. I would say maybe 1 or 2 mpg more if the driving habits stay the same.
I also wanted to say, my brother's LT Sedan was at 26mpg and I confronted him recently about this. He kept getting the cheap gas at Circle K and a member here pointed out to me that it is why my MPG went down due to the ethanol they use in the cheap gas.
It is not much less $ wise to get Shell, and the difference in mpg is drastic.
In fact, 2 days after he filled up with Shell 87 octane, he was up to 26.6mpg.
I know that a week from now he should be up there around 29mpg if he keeps using Shell.
I am also going to get him some fuel injector cleaner, Earnhardts has worked way better than all the brand I have used.
I have also thought highly of the Z Max, but it only works if your fuel system is really crudded up. It just gets you back to clean, and using it every 3000 miles is useless. Once every 30k miles perhaps, but not 3000 miles.
I used Z Max on my little Geo Storm and it had a big jump in mpg, but understand, the car was old. Someone using this in a new car is not going to clean much out as there is not much build up there anyways. That is why Z Max had a lawsuit against them, they falsly said they can increase everyones mpg, and it simply is not true. Same as trying to Seafoam an engine with 5k miles on it, useless.
THERE WILL BE PUNISHMENT!
Last edited by Mike85220; 12-02-2009 at 10:12 PM.
Reason: Automerged Doublepost