Shrinking gas mileage in 2007 Honda CRV

In the last 6 months my 07 CRV has been dropping in gas mileage. We used to get 26-27 mpg in the city, and 29-30 on the road. Now we’re getting 22 in town and 27 on the road.

I’ve had it to the shop twice and nothing is wrong. It seems to run fine as well. They’ve used computers to check it out.

Any ideas?

How many miles do you have on the odometer?
When did you last replace the spark plugs and the air filter?
Have you checked the pressure in your tires?
Did you recently purchase new tires?

About 60K
Air Filter @ 38945, no record of new plugs that I can find
Tire pressure good
Yes…new tires about a month ago.

Engine temp gets up to normal, no stuck thermostat? No, this would be more of a winter problem.

Maybe MPGs are going down with more AC use. Maybe your AC isn’t as efficient as it could be. Is it low on R134a? Are the belts all the correct tension?

Your new tires may have a higher rolling resistance than the original tires.
Did you check their rolling resistance rating prior to purchase of those tires?
The combination of tires with a higher rolling resistance, coupled with more A/C use, could account for the drop in gas mileage.

Also, check the Honda maintenance schedule to see when your spark plugs should be replaced.
They may be due at 60k.

Seeing how your car is rated for 20 MPG city and 27 MPG highway if you have a 2WD model and 19/26 if you have the AWD/4WD model, I’d say you’re doing pretty well for yourself. You appear to be getting exactly the kind of mileage your car is rated for. I doubt if there is anything really wrong with your car.

How are you measuring the mileage? Have you changed the way you measure it?

That’s because there may not be something wrong. As was previously said, using the A/C can significantly cut down on your gas mileage. Also, has traffic picked up in the city during the summer?

Just out of curiosity, what gas are you using? Are you using a major chain? I seriously doubt it, but there could be water in the fuel (but that is usually seen only in the winter). You could try a fuel treatment. There is a chance that you have some carbon deposits, but again, I doubt it. I think the reasons in the previous paragraph are far more likely.


Thanks so much. I’ll look into the tires. They’re better than original…Michelins, but I don’t know the resistance of either. This is the 3rd summer for the car…AC use didn’t have this much effect before…but I’ll look in to freon as well.

Thanks! I’ll check freon. Thermostat is fine…belts checked recently. I’ll check on that as well.

Agreed, though it was doing very much better before.

No…measuring as always. Not relying on computer, but “doing the math.” The computer happens to agree, however.

Using anything I run in to, basically. Rally, BP (ouch), anything. I thought at one point that the mileage suffered when it was routine to have ethanol in the gas, but nothing like this.

Thanks for everything. I have a good list to work on.

Thanks to everyone. I have a good list to work on.

I can’t see how low freon could cause this kind of thing. If your air conditioning is cold and working fine, leave it alone. Don’t encourage the shop to find something to fix that isn’t broken.

Recently, I discovered I could increase my fuel economy greatly on my motorcycle by shortening the time I let it warm up with the choke on. In fact, I have discovered that in summer Florida heat, I don’t need to use the choke at all, and my fuel economy has improved from 42 to 50 MPG.

The reason I mention this is that I recently noticed my friend “cooling down” her car before she loaded her children into it. She started the car, opened it up, and cranked the air conditioning. Then when the A/C started blowing cold, she closed the doors and gave the temperature a chance to drop before she loaded her kids into the car. Letting the car idle with the A/C blasting is definitely hurting her fuel economy. Could someone in your family be doing the same thing or something similar? Has your family recently expanded or undergone some other lifestyle change?

I am sure the new tires are part of the issue, but there are so many factors that could contribute to this kind of thing, you can never rule them all out. For example, have you started buying your fuel from a different station or pump than you used to use? Have you changed jobs or changed your route recently? Do you have a teenage driver who didn’t drive the car until recently? Could you have unintentionally switched from 100% gasoline to a mix of 90% gasoline and 10% ethanol? That is one of the most common culprits.

In conclusion, I wouldn’t assume something is wrong with your vehicle until you rule everything else out as a possible cause.

Right…the AC is cold. OK.

All worth thinking about…not many issues pertain. No teenagers…other family with odd driving habits…no change in route or gas stations except when traveling. I don’t have a choice at any station I visit not to have ethanol in the gas…wish I could find some pure gas, but don’t seem to be able to.

Actually the tires may be all or part of it. I’m not sure, but it seems that the problem may have begun with their installation. They don’t seem to be underinflated, but I’ll double check that. The low tire indicator doesn’t come on.


silly as this may sound, if your or your significant teen ager bumped the rt. frnt into the curb and bent the steering linkage, it would increase the two in and reduce the milage by raising the rolling resistance. When did you last have the alignment checked? Just guessing.

If you are relying only on the Tire Pressure Monitoring System (TPMS) to warn you of low tire pressure, then you yourself are part of the problem. You need to purchase a good quality dial-type pressure gauge and you need to check the tire pressure at least once a month. By the time that the TPMS notifies you of a drop in pressure, you could have wasted lots of gas.

That being said, it is very possible that the new tires have a higher rolling resistance than your old ones, but you still need to personally check the tire pressure on a regular basis.