So I bought this Jimmy 4x4 that has been sitting for 2 years, threw in a battery and she started right up. It's running rough, the CEL/SES is on and so is the battery light. I went to plug in my OBD2 computer but it says the connection failed, tried a different one and same thing. Anyone have any idea as to why this is happening? What should I check for? Thanks in advance.
