Possible transmission problem.

Please, help me to fix this problem: my van has an excessively high idle speed and when I driving it I hear a clunk when it shifts.

Please, help me to fix this problem: my van has an excessively high idle speed and when I driving it I hear a clunk when it shifts.
is a check engine light on? are all the wiring harnesses connected, secured? can you throttle it down at the air intake by hand?

Please, help me to fix this problem: my van has an excessively high idle speed and when I driving it I hear a clunk when it shifts.
josegom, Greg123 had a good idea about the high idle. May I suggest you check your motor mounts for the clunking sound. I have a 94 Villager with 130K miles and recently replaced the motor mounts which I thought was a transmission problem. I called several places and none of them ever had any complaints about Villager transmissions. A very easy way to see if it is the motor mounts, please don't be insulted if you already know how to do this, place car in gear (fwd or rev), put one foot on brake and rev the car a little bit off and on. If you need motor mounts, like I did, the engine will raise up about 4 inches then go back down. My motor mounts were absolutely wasted. Just for your info, there are 3 mounts, one on the l/h front side, one on the r/h front side and one in the rear of the engine just right of center. The two front one are easily accessible, the rear one is not. My rear mount was still ok so I left it alone. I only suggest this because like you I was just sure I had a transmission problem but luckily it wasn't. Good luck !!!!!!!!!!!

Is it a high mileage van? Whats the year?

I had a shift problem, see "95 slow shift out of gear thread" It was a bad TPS..