Hi everyone, I am getting a dismal 13 or 14MPG in town with my car, G6 GTP 2006 3.9L. I use to get 18 or better in town and I don't believe I have been driving it hard or any different than before. I don't seem to have a problem with gas mileage on the road.
I have been using 89 octane (w/ethonal) and went back to 87 octane to see if that made a different, but it hasn't changed the MPG.
Does anyone have any recommend fuel additives that you have tried to clean out the engine? This car is located/driven in the upper midwest and idling to warm up in the winter is an everyday occurence. This is the first winter I have had this car so there may be some build-up that I need to clean out.
Thanks for any input!
The best thing you can do is to get a PCM tune from Vector Motorsports.
I was having exactly your MPG on a 10 miles daily comute at 40 mph on flat road. Not only adds performance, also adds some MPGs too!
Now I am at 16.3 to 16.9 range, depending on traffic conditions
Also, it helps to add some extra psi to your tires, my coupe is at 35 psi all around and I am constantly checking. Synthetic oil, high performance filter and use cruise control whenever possible.
Next is weight reduction.... belive or not, I removed my spare and jack, but added a small air compressor and a can of Fix-a-Flat. I dont carry any junk.
I am waiting for my warranty to expire to futher reduce my car weight..... till then....good luck