gas mileage drop??

[kevintomb]

My 03 camry ( 4cyl auto ) used to get about 27-28 MPG in all around driving. The last couple times I checked mileage, it seemed to drop a significant amount. The tires are inflated correctly, and nothing seems wrong, other than I notice a good amount of pinging on some occasions. The spark plugs are original, as is everything on the engine (( 42,000 miles )) and it seems to run flawlessly and smoothly. Engine oil is up to level also, and no I dont drive differently. I attribute part of the drop to it being winter in western Pa, but the cold temperatures cant account for such a large drop. The last 2 times I did my mileage check I got 21.5 and 19.9, when as stated above I was regularly getting around 27-28. Any suggestions would help. The temperature has recently gone up here, so of course this next tankful mite be a somewhat more representative or normal driving 50-60 degrees, as opposed to the sub freezing levels from the 2 mentioned lower mileages.

[leasaunce]

if the weather is hotter, the car uses more fuel (in my own opinion)

have you service the car lately?

[kevintomb]

Originally Posted by leasaunce

if the weather is hotter, the car uses more fuel (in my own opinion)

have you service the car lately?

Well, as I said this is a rather abrupt change in mileage, so im doubting service ( which would include exactly what to you? ) would account for it. As for cold, when it is 20 degrees, the engine does not come up to operating temperature for MANY minutes of driving and the transmission doesnt follow the same shift schedule. (( it wont shift into 4th gear nor will the torque converter lock)) so that AUTOMATICALLY makes it less efficient in sub freezing temperatures. Im goint to change spark plugs and the air filter anyways (( neither look bad at all)) just to be sure, but this isnt exactly an old poorly maintained car.

[tacojet]

I have a '97 with the 5SFE (4cyl). I noticed a drop in mileage at about 100K miles. I changed out the O2 sensor on the exhaust manifold. Mine is a Cali car so it is called an Air/Fuel sensor, it does the same thing though. The milage went back to normal.

I picked mine up online for 75 dollars from a dealer in Indy (can't remember who though). My local dealer wanted 129 for it. At 41K miles the emmisions may still fall under the factory warranty, I would go to the dealer first and see.

[V(Sportivo)6]

Heh.....part of the reduction could be from the follwing:

The airconditioning off during the cooler climate?
The rubber tires have less internal friction (depends how cold your talking??)
Greater o2 intake ---cooler air
Engine wearing in

[Super Kaioken]

the engine doesn't engage Overdrive you mean? Check your antifreeze =X but if you're not engaging Overdrive.......that means you'll definitely be revving higher and losing gas.

[CamrySExxx]

do your heat your car up before driving ?

[kevintomb]

I warm my car up for about 1 minute, so that wont account for a huge drop in mileage. I do make a lot of short trips, so I DO REALIZE thats accounting for some of the drop lately. I just changed the oil, spark plugs, and cleaned the air filter ( which honestly wasnt very dirty at all) and now the temperature is MUCH warmer (( 50-70 )) so im gonna let my next tank of gas be my test, to see what happens. as for recomendations on an O2 senson, im kinda thinking its a bit early for one, with only 42K miles on car. I do notice the engine has been pinging a good bit lately also.

[tarbasd]

The pinging could be from bad timing and it does increase your mileage. I have a Gen3 (and I don't know anything about the newer ones), so maybe I'm totally wrong. Maybe the alternator was moved a bit and that ruins ignition timing from one moment to the other. Check your timing or have it checked.