Bumper to Bumper Radio, the car guys on KTAR, 92.3 FM in Phoenix, AZ, broadcast every Saturday from 11:00 am to noon. On this show, Dave Riccio of Tri-City Transmission in Tempe, AZ talks about AC service and the health of your vehicle's cooling system during the hottest days of the year. Also on this show:

• Do you need to wait for a symptom of AC failure before servicing?
• How low can your refrigerant be before you notice a loss of cool air?
• What are the symptoms of a coolant leak?
• How often should you replace your cabin air filter in the Phoenix area?
• What methods do auto repair shops use to find a leak in your vehicle?
• 1970 Chevrolet Nova: In a climate controlled environment, how long will tire lasts?
• 2000 Chevrolet S10: My check engine light has recently come on for the first time. I replaced most components of my cooling system and the code went away for a few days. Now the code has come back on – what should I try next?
• 2003 Mazda Miata: My temperature gauge began rising during a recent trip North. What is the most common reason for this and how can I best diagnose it?
• 2011 Chevrolet Impala: My AC switch seems to only work on certain settings. What are the steps to diagnosing this?
• 2007 Ford Focus: After replacing the battery 8 months ago, my battery light has begun coming on intermittently. Is this a problem with the ground cable?
• 2010 Chevrolet Cobalt: After returning from a road trip, my AC seems to be struggling. What do you think would be the most common reason for this?
• 2007 Dodge Ram: While pulling a trailer to Northern California, our AC began blowing warm air. Shortly thereafter the check engine light came on. Are these issues related?
• 2017 Ford Expedition: My truck is giving a mysterious mix of error codes. Where should I begin diagnosing the problem here?

Cars talked about on this show are the 1970 Chevrolet Nova, 2000 Chevrolet S10, 2003 Mazda Miata, 2011 Chevrolet Impala, 2007 Ford Focus, 2010 Chevrolet Cobalt, 2007 Dodge Ram, and the 2017 Ford Expedition.