sometimes when i start my car and dont let it warm up ill be driving and when im stopped the rpm gauge will jump up and down. It sounds like its revving and its dropping and it wont stop till i turn the car off and turn it back on. Engine d16a6 manual trans

 

did you try cleaning the iacv and adjusting the fitv screw all the way down?

 

nope dunno how noob status

 

search iacv and fitv, you will find the answers

 

IACV for sure