Transmission or sensor ??? Please help
I have a 07 Cherokee Laredo with 52,000 miles. I have just recently been experiencing a problem I think it's the transmission. When I engage it into drive from park or reverse, the " P,R,N,D would enlarge slightly and when I hit the gas pedal it want go, the rpm's won't rev. I would have to either shut the vehicle off or put it in neutral in order to work. This method is only a temporary relief. Today the engine light came on while on the freeway had the same problem. Took it to the mechanic hooked up his computer to diagnose it. He told me that it's not giving him any negative readings. He reset the system after I shut the vehicle off and turned it back on. The engine light came back on, again he tried to diagnose it again and it didn't give him any codes or negative results. He reset it again and apologized to me that he can not help me. Pleeeease help !!!!