I'm going to have another member here do the repair work, but he asked me to take the car into a dealership for a diagnosis since he lacks equipment to do it. So I'm looking for a place in the Phoenix area (I live in Tempe, will travel to the west side if they have courtesy cars). Anybody got a good suggestion where I can get a proper, and hopefully inexpensive diagnosis?

Symptom: my engine is making a weird ticking noise at varying speeds of varying volumes... I also have a P0442 code, though I don't think they are related... The car drives fine, but it's freaking me out... my car is stock except for the custom stereo, and just passed 150,000 miles. No other mechanical issues (that were major ie. i couldn't fix myself)...

All input welcome, thanks!!