Gas Mileage Drop

[ChuckK]

I just took two round trips from Golden to Fort Collins this weekend (kid's swim meet) and saw my highway gas mileage drop from my customary 27 mpg down to 24 mpg. The car now has 24,000 miles on it. I'll wait till the tires cool down to check the tire pressure to see if that's the culprit. The tires are relatively new and have given me 27 mpg on a long highway trip as recently as November. I guess I'll also check the air filter. Does anyone have any other ideas?

[BillAileo]

I remember reading, probably in a prior thread on this forum, that the winter versions of gasoline sold in many places in the U.S. deliver less MPG than the normal versions. Perhaps that has contributed to your recent lower MPG.

Bill

[ChuckK]

Hmm, good point. I think the gasoline I used in November probably was an ethanol blend, but I'm not sure. In Denver they used to use ethanol blends just in the winter months to avoid smog during periods of temperature inversion. I haven't kept up with how often ethanol is being used, but I was thinking they were using it all year now. I will check into that. Thanks.

[Tom H]

I noticed this same thing on my 04'. Highway went from avg of 28mpg to around 22. City/country went from avg 22mpg to 17. The car also began to idle very rough when the temp gets below 30 degrees F. I assumed it was related to the winter fuels used here in the Chicagoland area.

[berklee46]

I've been getting just under 15 city lately...

[Queens_VolvoXC70]

In addition to what everyone else has said, your fuel injector might also be a bit clogged. You might want to try Lucas Fuel Injector cleaner.
---

[wgriswold]

I read in the paper today that new hybrids are not coming even close to the EPA mpg estimates. Three of them got in the low twenties in mixed highway/city driving during tests with the reviewers. They blamed the defrost and AC mode which prevented the gas engines from turning off. Since I last reset the computer (about a year ago) I am getting 23.5 mpg with an average speed of 31 mph. Most (about 90%) of that time I was driving in town. I'm really happy with my mileage, especially compared with the new hybrid technology.

[jbl]

You might save some fuel if you exchange the sparkplugs and air filter.

[ChuckK]

Thanks for the suggestions. I'm going to wait till we have warm weather and better gas. If mileage doesn't go back up, I'll try the air filter, fuel injector cleaner, and new plugs, probably in that order.

Not sure what's going on with the hybrids that were mentioned. I have several colleagues with Toyota Priuses. They get 50+ miles per gallon in warm weather. They do "only" get in the 40's in the winter due to decreased battery performance and maybe the gas. I'm very close to buying one. Not to save gas money (even at $3 a gallon, it still doesn't make economic sense) but from an environmental standpoint. If I could only put a Volvo seat in one. I personally believe the Toyota full hybrid IS the car of the future. Fuel cells are just way too expensive and are being oversold (for various reasons) as a future technology. I think the hybrid will evolve into a plug-in hybrid that you can recharge overnight and eventually to a mostly electric vehicle as the batteries improve.