Honda engines have always been known as being reliable, fuel-efficient, and high-revving. Those three adjectives work very well when describing the K-Series engine, which first appeared in 2001. That engine has shown up in many different Honda and Acura products over the past 20 years, which leads us to believe that it is indeed reliable. But just how reliable is it?

Which cars did the K-Series engine come in?

If you’re unfamiliar with the Honda K-Series engine, then you’ll need to know that there are two different engines in the series: the K20 and the K24. Fortunately, Honda makes things easy on everyone by designating the engine size to correspond with the engine code. So “K20” is for the 2.0-liter engines and “K24” refers to the 2.4-liter variety.

The K20 engine

The K20 engine originally hit the U.S. market back in 2002 as it was nestled in between the fenders of the Civic Si, RSX, and CR-V during that time. The main engines to pay attention to are the K20A2 and K20A3 engine as every K20 engine is a slight derivative of one of those two, reports Drifted. The K20A2 engine, which can be found in the 02-06 Acura RSX, featured a high 11.0:1 compression ratio and i-VTEC technology, which netted a rating of 200 hp at 7,400 rpm and 142 lb-ft of torque.

The K20A3 engine could be found in the 2002-05 Civic Si and featured a low 9.6:1 compression ratio and an i-VTEC system, but only on the intake side. That led to a lower 160-hp and 141 lb-ft ratings, however, it’s still a good engine in its own right.

The K24 engine

The K24 engine, on the other hand, was made for fuel economy and low-end torque. As such, you’ll find derivatives of the K24 engine in various platforms like the 2002-09 Honda CR-V, 2004-08 Acura TSX, 2003-11 Honda Element, and 03-up Honda Accord.

Most K24 engines put out less than 200 hp and have a 9.6:1 compression ratio as they are set up for everyday efficiency. However, many Honda tuners will turn to the K24A2 engine that was found in the Acura TSX. That engine has a higher compression and better flowing components, which net it a horsepower rating of 205 and 164 lb-ft of torque.

There are 3 common issues with the K-Series engine

Now that we have a brief understanding of the different K-Series engines, it’s time to look into any potential issues. If you happen to own of the aforementioned cars with a K20 or K24, or you are planning to swap one of these engines into a different platform, then there are three common issues you should know about, according to Tuning Pro.

• Front crankshaft seal oil leaks: Also known as the “front main seal,” which is located between the crankshaft and the timing chain cover. Along with the rear main seal, this front seal is known for developing leaks even when the engine has less than 100,000 miles on it. If your car has oil leaks or if you smell burning oil, then it could be time to replace this seal.
• Exhaust camshaft galling: The exhaust camshaft in some K-series engines can experience “galling due to excessive friction on the cam lobes. This is typically due to a poor oil change history or poor-quality oil. If your car experiences power loss or if you hear a clicking noise from the engine, this could be the issue.
• Excessive engine vibrations: K-series engines are known to vibrate excessively. However, simple maintenance items like new spark plugs and wires can cut that down. If not, then your car’s engine mounts might need to be replaced.

How reliable is the K-series engine?

Overall, any K-series engine, whether it’s a K20 or K24, should be dead-on reliable for at least 200,000 miles. There are plenty of Acura RSXs and Honda Accord from the early 2000s driving around without much issue nowadays. Of course, routine maintenance is key, just like any other engine, and if you have a high-revving K20A2, then it’s important to keep an eye on the oil level every so often.

Otherwise, whether you currently own a Honda or Acura with a K-series engine or you plan on swapping one into another car, then you can rest assured that it will be powerful, fuel-efficient, and, most importantly, reliable.