Crack, BANG, PANG, while crusing,

[Imponator]

Got a -97 Explorer, when crusing it feels like the car was hit by a big hammer.
Once every five ten minutes. In the beginning, once each 25 minute and then around 55 mph, now even in around 30.
If I make a very short jerk on the gaspedal, it feels like the bang I have in the car. The problem is during crusing, had never appeard in acceleration.
It might be connected to the speed around going down in gear.
The engine runs calm.


Please help if you can, and exuse me for my bad English, I am Swedish.

Sincerarly Mats Edstrom

 

[matt98sport]

Does it do it when your slowing down, or when you are at a constant speed?
I could think of one thing = if its when slowing down, try cleaning your IAC valve because your motor might be idling too high when slowing down, and your tranmission is trying to downshift with engine under load whilst deaccelerating.
Mine started doing then, and im not one to enjoy loud gear engagement bangs comming from the transmission, so i fixed my idling problem (it would actually seem to go into warm up mode like when i first start it up) by cleaning the IAC which was absolutely filthy

 

[Imponator]

Hi, and a big thanks for your kindness to help me. My problem is often when I go to cruice after a acceleration, mostly up to the highest gear, then cruice. But now even if I slow down just a little. So hopefully I do have the same problem as you. Where do I find the IAC valve? Easy to clean?

Thanks / Mats