Watch Out for These Common Air Conditioner Problems

Admin • August 21, 2020
Car Airconditioner — York, PA — C. R. Smith Radiator & Auto Repair
Your car's air conditioning system works much like the HVAC system in your home. Its ability to turn refrigerant gas into a high-pressure liquid (and then back into gas again) pulls heat and moisture out of the air before the system pushes the cooled air into your vents.

Unfortunately, this complex system features multiple parts that must all work together efficiently. A failure in any component can cause your car's air conditioner to lose some or all of its cooling ability. This same complexity can also add time and effort to the troubleshooting process.

Here are some common air conditioning problems, along with their telltale symptoms, to help you narrow down the possible causes of your air conditioning woes.

Mold or Mildew Infiltration in the Air Vents


As an air conditioner cools warm air, some of the air condenses into water. This water may land in your vents or evaporator drain tube and linger there long enough to grow mold. Mold infiltration in an air conditioning system creates the same musty smell as it does in the home. It may also trigger allergic reactions.


You may encounter a similarly musty smell due to the presence of bacteria. Like mold, mildew thrives on moist surfaces such as evaporators. The older the car, the more bacteria its evaporator and drain tube may harbor.


The first to combat this unpleasant issue involves locating where the mold or mildew is hidden. Your technician may then apply anti-bacterial or anti-fungal treatments directly to the evaporator surfaces. Your blower ducts or drain tube may also need to be thoroughly cleaned with these products. 

Faulty Switches and Relays

Sometimes a car air conditioner will seem to work for brief periods before it loses cooling power and finally blows nothing but warm air. This on-and-off performance may stem from a switch, relay, or other component that has started to fail intermittently.


These failures may occur simply because the electrical system has stopped feeding them consistent power. For instance, electrical issues may affect connections with the compressor clutch, compressor clutch relay, AC control switch, or low-pressure cutout switch. (Of course, direct failure in any of these structures can also cause loss of cooling.)


Your air conditioner can only function properly when it receives the proper instructions and data. If your air conditioner works only some of the time or never works at all, diagnostic testing may reveal that you need a new temperature sensor or control module.

Refrigerant Leaks


An air conditioner can't refrigerate air without refrigerant. Refrigerant commonly leaks at a very slow rate through tiny holes in air conditioner hoses and seals. When the leakage seriously lowers your refrigerant level, however, you will notice that your car never gets as cool as it once did, even at maximum power.


Less commonly, an air conditioner fitting, seal, or hose can experience a total failure all of a sudden. When this happens, you may hear a hissing noise or even see white smoke emerging from beneath the hood.


If testing doesn't reveal any major problems in your hoses or seals, you may simply need to refill the system's refrigerant to a normal level. If you have a significant leak anywhere in the system, you must get that part repaired or replaced before you can get any long-term benefit from fresh refrigerant.

Compressor Failure



When the compressor in your car's air conditioning system develops a problem, the system can no longer move refrigerant through it under the proper pressure, which makes cooling impossible. Unlike some other air conditioning problems, a bad compressor will alert you to its condition with strange noises.



Compressors depend on moving parts such as belts and bearings to help them perform their essential functions. When one of these components fails, the resulting friction will often create a loud squealing or grinding noise. When these symptoms occur alongside a loss of cooling ability, suspect the compressor parts.



Car air conditioners can develop some confusing problems, but our auto shop can help. Contact C. R. Smith Radiator & Auto Repair to learn more.

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Your transmission is one of the hardest-working parts of your vehicle, shifting gears thousands of times on every drive to keep power moving smoothly from your engine to your wheels. When something goes wrong, it rarely happens without warning. At C. R. Smith Radiator & Auto Repair, we help drivers throughout York, Dallastown, Dover, and Spring Grove, PA catch transmission problems early, before a minor issue turns into a costly rebuild or replacement. Here are the warning signs to watch for. 1. Slipping Gears If your engine revs higher than usual without a matching increase in speed, or your car seems to hesitate between gears, your transmission may be slipping. This is one of the clearest signs something needs attention. 2. Delayed or Rough Shifting A healthy transmission shifts smoothly and quickly. If you notice a delay when shifting from park to drive, or a hard clunk between gears, it's time to have it checked. 3. Unusual Noises Whining, humming, or clunking sounds while driving — especially when changing gears — often point to worn components inside the transmission. 4. Burning Smell A burnt odor usually means your transmission fluid is overheating or breaking down. Since transmission fluid lubricates and cools internal parts, this issue shouldn't be ignored. 5. Fluid Leaks Transmission fluid is typically bright red and has a distinct smell. Spots under your vehicle are an early sign of a leak that can lead to serious damage if left unaddressed. 6. Check Engine or Transmission Warning Light Modern vehicles are equipped with sensors that can detect transmission issues before you feel them. Don't ignore a dashboard warning light — a diagnostic scan can catch the problem early. 7. Grinding or Shaking Grinding sensations when shifting, or shaking while driving, often signal worn gears, clutch problems (in manual transmissions), or low fluid levels. 8. Trouble Shifting Into Gear Difficulty getting your vehicle into gear, or it popping out of gear unexpectedly, is a sign that shouldn't wait for a routine appointment. 9. Low Fluid Levels Transmission fluid keeps everything running cool and lubricated. Low levels — often due to a leak — can cause premature wear and overheating. Why Early Detection Matters Transmission repairs can range from a simple fluid service to a full rebuild, and the difference often comes down to how quickly the problem is caught. Regular maintenance and prompt attention to warning signs can save you thousands of dollars and keep your vehicle reliable for years to come. Schedule Transmission Service in York, PA If you've noticed any of these warning signs, don't wait for the problem to get worse. The certified technicians at C. R. Smith Radiator & Auto Repair proudly serve drivers in York, Dallastown, Dover, Spring Grove, and the surrounding communities with expert transmission diagnostics and repair. Call us today at (717) 792-9912 to schedule your appointment.
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