Honda K24 Engine: Generations, Reliability & Buyer’s Guide
The K24 refers to a family of engines, not just a single part number.
Honda built the K24 for fifteen model years and put it in more vehicles than almost any other 2.4-liter four-cylinder sold in the United States: the CR-V, Accord, Element, Civic Si, Acura TSX, and Acura ILX, from 2002 through 2017. That production run is precisely why replacing one goes wrong so often.
"K24" is a family name, not a part number. A K24A1 out of a 2004 CR-V and a K24Z3 out of a 2010 Accord share a displacement and almost nothing else: different compression ratios, camshaft profiles, intake manifolds, harness connectors, and ECU calibration. Order on displacement alone and you get a box that bolts to nothing.
Honda K24 Engine Generation Overview
Variant | Years | Application | Output | Notes |
K24A1 | 2002–2006 | Honda CR-V (US) | 160 hp / 162 lb-ft | 9.6:1 compression. No VTEC on exhaust cam. |
K24A2 | 2004–2008 | Acura TSX (US) | 200 hp / 164 lb-ft | 10.5:1. VTEC on both cams. Most sought-after. |
K24A4 | 2003–2007 | Honda Accord, Element | 160 hp / 161 lb-ft | 9.7:1. Torque-biased workhorse. |
K24A8 | 2006–2011 | Honda Accord, Element | 166 hp / 160 lb-ft | 9.7:1. Revised calibration. |
K24Z1 | 2007–2009 | Honda CR-V (3rd gen, RE3/RE4) | 166 hp / 161 lb-ft | Z-series debut. Revised intake ports. |
K24Z2 | 2008–2012 | Honda Accord LX / LX-P | 177 hp / 161 lb-ft | 10.5:1 compression. |
K24Z3 | 2008–2014 | Honda Accord EX/EX-L, Acura TSX | 190–201 hp / 162–172 lb-ft | 11.0:1. High-output Z-series. |
K24Z6 | 2010–2014 | Honda CR-V | 180–185 hp / 161–163 lb-ft | Late CR-V application. |
K24Z7 | 2012–2015 | Honda Civic Si, Acura ILX 2.4 | 201–205 hp / 170–174 lb-ft | final |
K24W / W7 | 2013–2017 | Honda Accord, CR-V / Acura TLX | 185–206 hp / 181–182 lb-ft | Earth Dreams. Direct injection. |
The variant code matters more than the year. A K24A1 and a K24Z3 are not the same swap even if they came from the same decade.
Honda K24 Engine Generations Explained
K24A Series (2002–2011)
The K24A is the foundation of the family. Every K24A uses port fuel injection and Honda’s i-VTEC variable cam timing on the intake camshaft paired with a two-stage VTEC lift profile. The detail buyers miss is that base variants run VTEC on the intake cam only. The K24A1 in the 2002–2006 CR-V makes 160 hp on 9.6:1 compression and carries no VTEC mechanism on the exhaust cam at all.
The K24A2 in the 2004–2008 Acura TSX makes 200 hp because Honda raised compression to 10.5:1, fitted more aggressive camshafts, added VTEC to the exhaust side, and used a different intake manifold. Same displacement, different engine. The K24A4 (160 hp, 2003–2007 Accord and Element) and K24A8 (166 hp, 2006–2011 Accord and Element) sit in the middle as torque-biased workhorses. "K24A" on a listing is incomplete information.
K24Z Series (2007–2015)
Honda revised the platform with the Z-series in 2007. The K24Z1 arrived in the third-generation CR-V (RE3/RE4) at 166 hp, followed by the K24Z2 in the 2008–2012 Accord LX at 177 hp on 10.5:1 compression. The K24Z3, the high-output Accord EX and later TSX unit, runs 11.0:1 and makes 190 hp in Accord trim and up to 201 hp in the TSX.
The K24Z7 closes out the naturally aspirated DOHC K24 in the 2012–2015 Civic Si and 2013–2015 Acura ILX at 201 hp. Z-series engines carry different accessory brackets and harness connectors than A-series units and are not drop-in replacements across trims. This is where most budget builds chasing the best used engines for swaps go wrong.
K24W Earth Dreams (2013–2017)
The K24W is Honda’s direct-injection K24, and it breaks compatibility with everything before it. Direct injection requires a camshaft-driven high-pressure fuel pump, a different cylinder head, and a fuel system the port-injected K24A and K24Z do not have. The K24W makes 185 hp in the Accord and CR-V; the K24W7 in the Acura TLX makes 206 hp. If your vehicle came with a K24W, you should replace it with a K24W.
K24 Reliability: The Real Record
The Honda K24 is one of the most durable 2.4-liter four-cylinders Honda has built. Well-maintained units routinely reach 200,000 to 300,000 miles before needing internal work, and the failure points that exist are maintenance-driven rather than design defects.
Oil consumption. The K24 does not consume oil under normal service. When an engine burns oil, the cause is almost always worn piston rings or a stretched oil change interval that lets deposits build on the ring lands. Ask for maintenance records on any K24 above 120,000 miles.
Timing chain and tensioner. The K24 runs a timing chain rather than a belt designed to last the life of the engine, so there is no scheduled replacement interval. Chain noise points to a worn hydraulic tensioner rather than a stretched chain, and it presents as a metallic rattle on cold start that quiets once oil pressure builds.
VTC actuator. This issue is the K24’s best-documented fault. Honda issued service bulletin A09-010 covering the 2008–2012 Accord, 2012–2013 CR-V, and 2012–2013 Crosstour for a loud rattle lasting roughly two seconds at cold start-up, naming a defective variable valve timing control (VTC) actuator as the cause. The solution is a VTC actuator replacement that does not require pulling the full cam chain assembly. A two-second cold-start rattle on a K24 is repairable, but price it in before you buy.
Head gasket. K24 head gasket failure is uncommon, and when it happens, an overheating event caused it. A K24 with a blown head gasket almost always has a cooling system failure behind it, which means the same engine may have warped a head or scored a cylinder wall. Treat it as a symptom, not the whole problem. The K24’s weak points are wear items with known part numbers, not architectural flaws.
K24 Compatibility: Which Vehicles Use It
Vehicle | Years (US market) | K24 Variant |
2003–2017 | K24A4, K24A8, K24Z2, K24Z3, K24W | |
2002–2016 | K24A1, K24Z1, K24Z6, K24W | |
2003–2011 | K24A4, K24A8 | |
Honda Civic Si | 2012–2015 | K24Z7 |
Acura TSX | 2004–2014 | K24A2, K24Z3 |
Acura ILX 2.4 | 2013–2015 | K24Z7 |
Acura TLX 2.4 | 2015–2020 | K24W7 |
This chart tells you which family a vehicle belonged to. This chart does not mean that any engine listed in a row can be installed in any year corresponding to that row. A K24Z7 out of a Civic Si will not run correctly in a 2009 Accord without ECU and harness changes, and a K24W will not run in anything built before 2013. Fitment is determined by the precise variant code that corresponds to your vehicle's build data, rather than the displacement inscribed on the valve cover. Please conduct an engine fitment check before committing to any unit.
What to Check Before Buying a Used K24
1. Confirm the variant code, not the displacement. The K24 code is stamped on the front of the block near the oil pan rail. Please obtain a photograph before agreeing to anything and then cross-reference it with the donor VIN. If you are unsure which variant your vehicle takes, decode your VIN first; the eighth character identifies the engine.
2. Get a cold-start video. Both K24 rattles that matter, the VTC actuator and the chain tensioner,, appear only on a genuine cold start and fade within 30 to 60 seconds. A seller who refuses to send one is not worth the risk. This is the highest-value step in any used engine inspection.
3. Read the oil at the dipstick. Dark brown is normal. "Black and sludged" means stretched oil intervals, and the VTC actuator and tensioner absorbed that damage first. "Milky" or "foamy" means coolant in the oil. Walk away.
4. Ask for compression numbers. A healthy K24 reads in the 170–190 psi range when warm. The spread matters more than the absolute figure: no cylinder should fall more than 15% below the highest reading. Multiply the highest by 0.85; anything under that will misfire.
5. Confirm what actually ships with it. A complete K24 should arrive with the intake manifold, alternator, power steering pump, A/C compressor bracket, and sensors. A bare long block costs real money to complete, and that cost never appears in the listing price.
6. Establish JDM or domestic sourcing, and get it documented. Japan’s shaken inspection regime pushes vehicles off the road at low mileage, so JDM K24 units frequently carry lower verified mileage than US-market equivalents, but that only counts when the sourcing is documented. This is where crate, remanufactured, and OEM used engines separate, an OEM used K24 is the unit Honda built, but a rebuild is someone else’s interpretation of it.
Sourcing a K24 engine with the code confirmed is essential.
Blue Prism Automotive supplies OEM used Honda K24 engines, including JDM-sourced units. We match the donor variant code against your vehicle before a unit ships, not after it arrives. Every listing carries a confirmed code and documented mileage. We do not sell aftermarket rebuilds, and we never list a "2.4L Honda" without telling you whether it is an A1, an A8, a Z3, or a W. Call with your VIN, and we will confirm the exact variant your vehicle takes before you spend anything.
FAQ
What is the Honda K24 engine?
The Honda K24 is a 2.4-liter inline-four from Honda’s K-series family, produced from 2002 to 2017. It uses a DOHC 16-valve aluminum design with i-VTEC variable valve timing and a timing chain, and Honda fitted it to the Accord, CR-V, Element, Civic Si, Acura TSX, and Acura ILX.
What vehicles use the Honda K24 engine?
In the US market the K24 appears in the Honda Accord (2003–2017), CR-V (2002–2016), Element (2003–2011), Civic Si (2012–2015), Acura TSX (2004–2014), Acura ILX 2.4 (2013–2015), and Acura TLX 2.4 (2015–2020). Each uses a different variant code, so the vehicle alone does not identify the engine you need.
Is the Honda K24 engine reliable?
Yes. The K24 is among the most reliable naturally aspirated 2.4-liter engines built between 2002 and 2017, with well-maintained examples reaching 200,000 to 300,000 miles. Its known faults, VTC actuator rattle and timing chain tensioner wear, are K24A2 maintenance-driven and repairable, not engine-ending design failures.
What is the difference between K24A, K24Z, and K24W?
The K24A (2002–2011) and K24Z (2007–2015) are both port-injected, but the Z-series uses revised intake ports, higher compression, and different accessory brackets and harness connectors. The K24W (2013–2017) is the Earth Dreams direct-injection version and needs a high-pressure fuel pump the earlier engines lack, so it is not interchangeable with either.
How many miles does a Honda K24 engine last?
A maintained K24 typically lasts 200,000 to 300,000 miles. Consistent oil changes are the deciding factor, because the VTC actuator and chain tensioner suffer first from extended intervals. Any unit above 120,000 miles should come with maintenance records.
What are the common problems with the K24 engine?
Three issues are documented: VTC actuator rattle at cold start, covered by Honda service bulletin A09-010; timing chain tensioner wear, which produces a similar cold-start rattle; and oil consumption on high-mileage units with worn piston rings. Head gasket failure is uncommon and almost always caused by overheating.
What is a K24A2, and why is it different from other K24 variants?
The K24A2 is the high-output K24A fitted to the 2004–2008 Acura TSX, rated at 200 hp. Honda gave it 10.5:1 compression, more aggressive camshafts, VTEC on both cams, and a different intake manifold. It is the most sought-after K24 variant and will not drop into a base Accord or CR-V without ECU and harness work.
Can I swap a K24Z into a vehicle that came with a K24A?
Not directly. Z-series engines use different intake port geometry, accessory brackets, and harness connectors than A-series units, and the ECU calibration differs. The swap is achievable with the right supporting parts and tuning, but it is not a drop-in. Replace a K24A with the same variant code whenever possible.
What should I look for when buying a used K24 engine?
Confirm the exact variant code stamped on the block, request a cold-start video to rule out VTC actuator and tensioner rattle, check the dipstick for sludge or coolant, and ask for compression numbers showing no cylinder more than 15% below the highest. Confirm which accessories ship with it and whether sourcing is JDM or domestic.
Where can I buy a used Honda K24 engine with verified fitment?
Blue Prism Automotive supplies OEM used Honda K24 engines with the variant code confirmed and mileage documented before shipping. Fitment is matched against your VIN before the unit leaves. Call with your VIN and the K24 variant your vehicle requires.
