I have 2002T&C with 3.8L awd with 112k miles. Van runs amazingly strong on flat ground and gets 21-22 mpg but while going uphill (anything above 20 degree incline) van feels poweless, I have to give lot of gas and motor at 3500-4000 rpm with tranny in 2ed gear to keep it at 35mph, it goesn't go above 35mph uphill no matter how hard i try.

Can any one share some suggestion on what could be wrong and if there is any easy fix?

 

Two things I would look at are fuel pressure and compression. If you're at higher altitudes could be a MAP sensor issue. Just stabs in the dark.

 

Why not try put the transmission in a lower gear range. 20 degree is a petty big incline.

 

To my knowledge public roads are typically no more than 12 degrees by code. So yes a 20 degree slope could only be a private driveway or something.

If you are having trouble with public road inclines and need 2nd gear and are getting only 35 mph, then I think you must have an issue. But.. your flat road performance seems decent at 21-22 mpg. Are you really driving up 20 degree inclines? If so then I think 2nd gear and 35mph is good for any car.

 

Hey , Your cataletic converter is stopped up or the exhaust pipe is mashed flat !! I've seem this a lot over my 63 years . When you hit the inclines your pedal goes to the floor , but the car just want go . I told this to a fellow 40 years ago . He had it checked an it was clear . I told him to check the y-pipe an there was 2 pipes one inside the other & the inside pipe had colapsed stopping most of the exhaust flow . my thoughts Bud