Get one!

Total fun toy and you never need to wonder what code is set. Also, you can look at any of up to 54 sensors that the PTCM is watching. I'd bet if you put an UG on your car, the "Coolant Temp" reading will be way high. This means that the PTCM is not at fault, the temp sensor is. Then, you order one and either change it yourself or take the car to a local trusted guy and just tell him, "Put this in." You pay no diagnostic fees. If it fixes it, fine. If not, you did not spend $2000, either.

But with the UG, you know so much more about what is going on than without it.

Mine is stuck to my windshield and snitching to me about what is going on with the car every time I drive.