Bad gas mileage

[slo5o]

I have a 99 explorer sport, 4wd 2 door ohv v6 and this thing is killing me in gas. I get 190 miles to a tank on average, truck runs great and no check engine light or codes. I dont drive like a maniac and never run it up past 3500 in any gear. I do all city driving, but not alot of stop and go if that makes sense. I have stock tires and wheels on it, 4.10 gears, and it has had plugs, wires, and air filter replaced recently. Any ideas?

 

[smiley1]

Clean the MAF sensor, new fuel filter, clean injectors, check for brake drag/lube caliper slide rails, run some sea foam through it, tire pressure, and IAC valve replacement if necessarry.

How many miles are on it?

 

[KC's Ford]

If you have over drive check to see if its working.

 

[slo5o]

Clean the MAF sensor, new fuel filter, clean injectors, check for brake drag/lube caliper slide rails, run some sea foam through it, tire pressure, and IAC valve replacement if necessarry.

How many miles are on it?

It has 92xxx miles on it. The idle does act a little weird compared to other cars Ive owned. When its cold it will not idle below 1500 rpm's and until the temp gauge gets to half way it wont idle below 1000 rpm's, takes a while before it will idle down right. I have the tire pressure at 38 psi on all four, I will clean the maf tommorrow and see if that helps. Thank you for the suggestions.

 

[slo5o]

If you have over drive check to see if its working.

Overdrive is working but I mostly drive 40mph and it doesnt shift into od until atleast 45.

 

[BrooklynBay]

Oxygen sensors are known to get "lazy" over time. They could get out of calibration, and eventually trigger an engine code. If they are old, they could get lazy, and just send a slightly out of wack signal to your computer. This would only throw off the mixture a little bit, and eat up your gas mileage. The coolant, and air charge temperature sensors could also affect mileage by throwing off the mixture, but would also affect starting. Some of the symptoms of an oxygen sensor before they start to show a code would be surging, which is also a scanning idle, hesitation, and poor gas mileage. The gas mileage problem might be due to this, even though it's not showing any other symptoms. A well tuned engine could get 11% better gas mileage according to the Chilton's car care manual.

 

[HardTech]

I have a 99 explorer sport, 4wd 2 door ohv v6 and this thing is killing me in gas. I get 190 miles to a tank on average, truck runs great and no check engine light or codes. I dont drive like a maniac and never run it up past 3500 in any gear.

In order to see good gas mileage you need to do no more than 2500 rmp thats getting on highway, and 2000 rpm in city.

I think even when i really need to get up on the highway I dont surpass 3000 rmp. So kinda driving like a maniac... Tone it down a bit and this should help