My 2007 Ranger (4 cyl, 2wd, auto) has developed a very annoying problem. When the truck is cold, the gas pedal takes a good amount of effort to push down. Once you get through the initial stiffness it moves fine. As soon as you let the pedal all the way out, it's tough to push down again. It gets worse as the temperatures outside fall. It also has only started doing this in the last few thousand miles. It gets slightly better as it warms up, but it's still noticeable.

I'm going to take it to the dealer and have them deal with it, but I would love to know what people think is causing this. Eventually the car will be outside of the warranty period, and I'll have to fix it.

Do you think I have a bum throttle body setup, or is it something easier to fix?

Thanks all, I'll let you know what the dealer does.

-Sean

 

lubricate the throttle body...

 

I had this problem when my truck was newer. The butterfly in the throttle body was closing too far and binding. Plastic shrinks and expands more than metal so when it is colder the problem is more noticeable.

The 4.0 SOHC throttle body has a stop adjustment screw for the butterfly linkage. I adjusted it a little to keep the butterfly from closing so much. The problem went away.

I don't know if the 4 cyl throttle body has an adjustment screw but it should not be difficult to find if it does have one. It looks like it is an idle adjustment screw but don't try to use it for that.