If you've ever had a car issue and mentioned it to someone else, you know that they immediately turn into an expert mechanic, explaining what the issue must be, despite the fact that they're an accountant sitting in the cubicle next to yours. Diagnosing vehicle issues can be confusing, especially since certain symptoms can have more than one cause. Here are some commonly misdiagnosed vehicle issues, and their alternative causes.
1) Engine Will Not Start
Common misdiagnosis: dead battery
Alternative diagnosis: alternator needs to be repaired/replaced
If a car doesn't start, most people automatically assume that the issue is a dead battery. While this is fairly accurate, it neglects to account for a reason as to why the battery may be dead. An issue with the alternator prevents the battery from being recharged while the car is running, causing the battery to discharge, so replacing a battery when there is an alternator issue won't help. Always make sure the alternator is checked in the event of a dead battery.
2) Check Engine Light Comes On
Common misdiagnosis: mechanical issues
Alternative diagnosis: gas cap is loose
When your check engine light comes on, you tend to assume the worst. But the light doesn't always mean that you're experiencing a serious mechanical issue, and quite frequently can be caused by something that's very benign, from a faulty sensor to a misfire code. The most benign (and often the most common) reason for a check engine to come on is a gas cap that hasn't been tightened properly by the driver. So before you start freaking out and totaling your repair bill in your head, check your gas cap first.
3) Vehicle pulls to one side while driving
Common misdiagnosis: the alignment is off
Alternative diagnosis: tire is deflated on one side
If your car is pulling to one side when you're driving, it's safe to assume that you need to get the car in for an alignment as soon as possible, right? Not necessarily. This is the case whether or not you hit any big potholes, as they can not only knock the car's alignment off, but can also cause your tires to get damaged or deflate. A tire with not enough air in it will cause your car to pull to the side, the same goes for a damaged tire. So before paying for an expensive alignment, check to make sure the tires are all in good shape.
4) The air conditioning isn't blowing cold enough
Common misdiagnosis: low refrigerant
Alternative misdiagnosis: refrigerant leak
The default diagnosis for an air conditioner that isn't blowing cold enough is typically low refrigerant. But simply adding more refrigerant to the car's system without checking the underlying causes can lead to expensive damage, especially if you overcharge. You need to check for a refrigerant leak first and foremost, and a qualified mechanic can do this by using high and low pressure guages to test the system.
5) Car is leaking fluid
Common misdiagnosis: engine oil leak
Alternative misdiagnosis: power steering fluid leak
If you're pulling out your garage or driveway and notice a darker fluid under the car, you usually assume that it's engine oil, and would describe it as such when asking for advice. However, power steering fluid is a very similar color to engine oil, and it's possible that it could be leaking. The key is to look for where exactly the leak is coming from, and also checking your power steering fluid levels along with your engine oil to see if they are running low. If the fluid is a bright color, it is likely to be coolant.
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