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Demystifying Car Diagnostic Codes: Simplify Repairs With TIRECRAFT

Today’s post explains 5 of the most common car diagnostic codes we see in the shop, then discusses whether or not it benefits drivers to invest in OBD-II readers for home use.

Read on to level-up your skills with recondite OBD-II readers, and find out why it is often more economical to leave car diagnostics to the pros, or contact your local TIRECRAFT for a free consultation.

Demystifying Car Diagnostic Codes: Top-5 OBD-II Code Meanings

These are the 5 most common car diagnostic codes we see in our shops:

1. Oxygen sensor—Car diagnostic code P0171-P0175. If you see these codes on your OBD-II reader, your vehicle’s oxygen sensor is on the fritz, which means your fuel efficiency isn’t great, and your vehicle could be at risk of stalling out on the road at random.

2. Engine misfire—Car diagnostic code P0300-P0305. The OBD-II system tracks engine misfires by monitoring the speed of the crankshaft while the engine is in motion. If one or more of your cylinders isn’t working properly, the crankshaft will experience a slight loss of speed, and you’ll see this code.

3. Evaporative system error—Car diagnostic codes P0411, P0440, P0442, P0446, and P0455. Your vehicle’s evaporation system (EVAP) seals the fuel system and prevents fuel vapors from escaping into the atmosphere. Driving with an EVAP leak is not recommended, as it is a major contributor to greenhouse gas emissions, and it can also interrupt the internal combustion process, leading to unpredictable stalls and start-up issues.

4. Exhaust gas recirculation (EGR)—Car diagnostic code P0401. Commonly known as the EGR, the exhaust gas recirculation system typically goes awry if the oil hasn’t been changed in awhile, or if you frequently drive your vehicle on short trips without allowing it to warm up, which causes harmful carbon buildup.

5. Catalytic converter—Car diagnostic codes P0420 and P0430. The catalytic converter can fail due to old age, improper fuel mixtures, bad spark plugs, malfunctioning oxygen sensors, and plenty of other reasons, all of which require different fixes and/or part replacements.

Make Time For Pro Car Diagnostics: Save More With TIRECRAFT

While it is helpful to know the common car diagnostic codes explained above, this knowledge won’t replace a professional car diagnostic service.

Why? Because while car diagnostics codes can give you a general idea of the problem area, they do not specify the cause or necessary repair. Think of these codes like your dashboard service lights—enough to tell you something’s wrong and what basic services may be needed, but not a detailed diagnosis. Therefore, even if you have the required tools and replacement parts, you’ll still need an expert’s eye to get to the root of the problem. Without one, your ODB-II reader won’t do you much good.

For these reasons, it is not necessary to invest in an OBD-II reader for your vehicle—it is much more economical to take your vehicle to your local TIRECRAFT for a professional car diagnostic.

Not only will you save yourself the equipment costs of an OBD-II reader, but you’ll also increase your odds of detecting other issues earlier, as every appointment gives your vehicle the benefit of the expert’s eye. Many of these issues, such as uneven tire wear or improper wheel balance, cannot be detected by OBD-II readers, and failing to spot them early can seriously shorten your tires’ tread life.

What’s more, if you sign up for the MyTIRECRAFT Rewards program, every visit and car diagnostic service will earn you rewards points that can be spent like cash to reduce the costs of future upkeep services, tire upgrades, and part replacements.

To get in touch with our car diagnostics experts, use the Find a TIRECRAFT tool.