[Siryet]

I have a 2005 ford ranger v6 auto a/c and it will drive down the road at 20mph on it's own without me touching the gas petal. This happens with or without the air on.
Needless to say that my gas millage is very poor around 18 in city and 21 highway under no load conditions.
Truck has 16,500 miles.

Dealer mechanic says this is normal and we will have to live with it.

Ok Ford owners Mechanics does this sound normal?

 

[morrowsmowers]

The vehicle is rated at 15 city and 24 country. You sound like your getting what it is rated for.

Ken in Glassboro, NJ

 

[wy_white_wolf]

2 or 4 WD?

We have a 2004 ranger 4X4 V6 with auto and air. Get 20 to 21 on the highway at 75 mph. Wife only gets around 10 to 12 in town. She gets road rage real easy and it kills her mileage in town.

There was 2 different v6s put in these. The larger one actually gets better mileage as it can handle the wieght better.

 

[chuckhole]

'05 with only 16.5k miles? Wow. You are doing pretty well to get that kind of mileage. How is your curb idle set? Does it idle pretty high? It sounds like it since you are getting 20mph at idle. It has been a long time since I was a mechanic but the same basic rules apply - flush the fluids and keep it clean. A clean engine runs better. Dirt, grease and grime will stick moving parts.

I used to have the 4-cyl Mazda B2500 (same a Ford Ranger) and the mileage on it was never good.......17-18mpg mixed use. I get that now with my Chevy 2500HD 4WD Crew Cab, 6.6L Duramax Diesel and 6-spd Allison tranny. I get 20mpg on the highway and I now have a much higher tow rating than the old Mazda. It couldn't even tow its own shadow. BTW, my 13 month old Chevy has 30k miles on it already.

 

[idahodave]

Fuel economy isn't too bad, but 20 mph without gas is a problem.

Could be a bad temperature sensor keeps the engine in the warmup mode even when it's up to operating temperature.

Is the idle speed high?

I'd find another dealer (if it't still under warranty) and see if the 20 mph without gas can be fixed.

 

[Beeman]

I have a 2005 ford ranger v6 auto a/c and it will drive down the road at 20mph on it's own without me touching the gas petal. This happens with or without the air on.
Needless to say that my gas millage is very poor around 18 in city and 21 highway under no load conditions.
Truck has 16,500 miles.

Dealer mechanic says this is normal and we will have to live with it.

Ok Ford owners Mechanics does this sound normal?

Idle problems on Ford fuel injected vehicles are pretty common. The throttle body plate needs cleaning periodically as part of normal maintenance. A bad seal at the air filter box or anywhere in the intake hose will suck dirt into the throttle body. Idle speed is controled by a solenoid that controls amount of air it letas in to keep idle correct. If the throttle plate is dirty and not closing properly it will cause idle problems. Also any type vacum leak that allows air in will increase idle speed that the computer cannot compensate for. Check these items first.
Fuel mileage sounds about right, Fords aren't known for great fuel mileage on their V-6 and V-8 engines.

 

[fixer1958]

I could agree with the vaccum leak but I would think it would flag the check engine light. Anything running amuck under the hood especially an 05 will flag the light.

Cleaning the throttle plate on a ford never stopped me even though the little sticker on the throat says not to. It's supposed to have a coating in there so as not to gum up. It doesn't work very well.

The mileage is about right, but the 20mph idle is odd without other problems.

 

[chuckhole]

If you want an easy way to find any type of vacum leak, this how I do it:

Turn on the engine and let it warm up to normal operating temperature. Take a can of carburator or throttlebody cleaner and spray all around the engine fuel components and vacum hoses. If any of these items is not sealed well or has a crack in it, it will suck the cleaner in along with the air and the idle speed of the engine will change. The engine will rev up a little bit when it sucks in the cleaner and you have hit the spot where there is a problem.