My car was surging and felt like the transmission was slipping everytime i got to around 2500 rpm the rpm hand would shoot up to around 4000 and then it hard shifts into gear. I had Autozone run a code check and it came up speed sensor. Has anyone else had this problem. I just had a chip installed a couple of days ago by apr. and thats when the problem began is the extra horsepower causing this problem. just trying to see if someone can help before make a 2 hr drive back to apr.