Honda K20 Engine Problems, Specs And Reliability

Honda initiated the production of K-series, 4-cylinder 4-cycle motors in 2001. Keeping dual overhead camshaft valvetrains, they reach lower attrition thanks to roller rockers. K-series motors employ a coil-on-plug ignition system without a distributor but featuring a coil for every spark plug.

Refraining from the application of a classic ignition timing system with a distributor, these motors feature a computer-controlled system, allowing the ECU to regulate ignition timings depending on sensor inputs. Cylinders featuring cast-iron inserts resemble the ones of B- and F-series motors, differing crucially from FRM cylinders in H- plus fresh F-lineup motors, applied in Honda S2000.

Like B-series motors, the K-lineup keeps 2 short blocks of identical construction, but with distinct deck heights. K20 deck height is 212 millimeters while K23 and K24 feature 231.5 millimeters decks.

K-lineup motors may feature two kinds of the brand’s i-VTEC system, having variable timing control on the intake cam. The VTEC system at such motors as K20A3 functions on the inlet cam alone; just 1 valve opens fully at low redline while the other opens partially for a better swirl effect in the combustion chamber, which contributes to enhanced fuel atomization.

At high redline, two inlet valves open completely allowing the motor to breathe. In such motors as K20A2, applied for Acura RSX Type-S, the VTEC system runs on both inlet and exhaust valves, letting them take advantage of numerous cam profiles. Moreover, an advanced variation of the K24 motor is employed for races, including Formula 3.

K20 Engine Specs

What Cars Have The K20 Engine?

• K20A
  2001–2006 Honda Civic Type R (JDM)
  2001–2006 Honda Integra Type R (JDM)
  2002–2008 Honda Accord Euro R (JDM)
  2007–2011 Honda Civic Type R (JDM)
• K20A1
  2001–2006 Honda Stream (RN3, FWD)
  2001–2006 Honda Stream (RN4, AWD)
• K20A2
  2001–2006 Honda Civic Type R (EDM)
  2002–2004 Acura RSX Type S
  2002–2004 Honda Integra Type R (AUDM/NZDM)
• K20A3
  2002–2006 Acura RSX
  2002–2005 Honda Civic Si
  2002–2005 Honda Civic SiR
  2002–2005 Honda Civic Type S
  2003–2006 Honda Civic 2.0 i-VTEC (SEA)
• K20A6
  2003–2006 Honda Accord (EDM)
  2003–2006 Honda Accord (ADM)
• K20C1
  2015–present Honda Civic Type R (EDM)
• K20C2
  2016–present Honda Civic LX (USDM)
  2016–present United States Formula 4 Championship
• K20C3
  2016–present Honda Avancier (China)
• K20C4
  2018–present Honda Accord

K20 Engine Modifications

1. K20A, released in 2001, is a sports modification for the Japanese domestic market. It reaches 220 horsepower at 8,000 rpm while torque is 215 Nm at 6,100 rpm. The cylinder block contains balancer shafts, a stronger crankshaft, high compression pistons (CR=11.5) plus strengthened connecting rods. Additionally, the motor features dual valve springs, vigorous camshafts, lighter flywheel, PRC intake manifold or RBC one for Euro R, enhanced header 4-2-1, 310 cc fuel injectors plus 54 millimeters exhaust system.K20A camshafts for the Japanese market keep such characteristics: intake 244/280/245 degrees and lift 8.84/12.65/9.68 millimeters; exhaust 240/278/244 degrees and lift 8.59/12.14/8.74 millimeters.
   The motor’s head porting is built in-house, keeping the 62-millimeters throttle body. In 2007, the motor was subjected to some alterations. Among the additions were a short RRC intake manifold, 64 millimeters throttle body, enhanced inlet plus exhaust head ports strengthened connecting rods. The compression index became equal to 11.7. Those alterations led to the VTEC system triggering at 5,800 rpm in lieu of 6,000 rpm. Moreover, K20A received a 4-2-1 short header plus a straighter exhaust system of 54 millimeters. Consequently, the output reached 225 horsepower at 8,000 rpm and torque of 215 Nm at 6,100 rpm while the revolutions limiter was launched at 8,000 rpm.
   Motor with these characteristics is available only at Civic Type R FD2, sold in Japan.
2. K20A1 has been already mentioned above. It reaches an output of 156 horsepower at 6,500 rpm and torque of 188 Nm at 4,000 rpm.
3. K20A2 is analogous to K20A, though it employs other camshafts plus PRB intake manifold. Camshafts have such specifications: intake 238/278/240 degrees and lift 7.36/12.42/7.82 millimeters; exhaust 240/280/242 degrees and lift 7.14/11.12/7.72 millimeters. The compression index equals to 11 while the i-VTEC system starts to operate at 5,800 rpm. The output is 201 horsepower at 7,400 rpm while torque is 193 Nm at 6,000 rpm while the revolution limiter is launched at 8,250 rpm. Moreover, the motor features 310 cc original fuel injectors.
4. K20A3 is almost identical to K20A1 but is utilized for Acura RSX (2002-2006) plus Honda Civic Si (2002-2005). Keeping 270 cc injectors, i-VTEC is launched at 2,200 rpm, and it also applies PPA intake manifold, triggered at 4,600 rpm. However, a 1-stage PRB intake manifold was utilized for Honda Civic Si.
5. K20A4 is a K20A3 modification, employed for USDM Honda Accord (2003-2007) plus Honda CR-V (2002-2006).
6. K20A6 is another modification of K20A3 but for Honda Accord (2003-2007), sold in Europe and Australia.
7. K20Z1 is a variation of K20A2, keeping a restyled intake system plus fresh exhaust manifold. Furthermore, it features more vigorous camshafts, allowing to reach 210 horsepower at 7,800 rpm and torque of 194 Nm at 6,200 rpm.
8. K20Z2 is a substitute to K20A, featuring a fresh longer runner intake manifold, restyled camshafts plus the Drive by wire mechanism. The output equals to 155 horsepower at 6,000 rpm with torque of 188 Nm at 4,500 rpm.
9. K20Z3 is a variation of K20Z1, but keeps other camshafts plus RRB intake manifold. Keeping the power of 197 horsepower at 7,800 rpm and torque of 188 Nm at 6,200 rpm, it was built for Honda Civic Si (2006-2011) plus Acura CSX Type S (2007-2010).
10. K20Z4 is a modification of K20Z3 for Civic Type R (2007-2010), sold in Europe. It reaches an output of 201 horsepower at 7,800 rpm and torque of 199 Nm at 6,800 rpm.
11. K20C1 is a motor with turbocharging, utilized for Honda Civic Type R (starting from 2015). It’s provided with fresh lightweight crankshaft, forged connecting rods plus restyled pistons with a compression index of 9.8. Additionally, it features a fresh cylinder head with direct injection plus i-VTEC system for inlet and exhaust valves. Honda enhanced inlet plus exhaust head ports, adding also a single-scroll MHI TD04 turbocharger, keeping the boost pressure of 23.2 psi (1.58 bar).
    The stated above updates allowed the motor to reach 310 horsepower at 6,500 rpm and torque of 400 Nm at 2,500-4,500 rpm with the revolution limit equal to 7,000 rpm.
12. K20C2, a naturally aspirated variant of K20C, was built for Honda Civic (starting from 2016). It keeps a redesigned i-VTEC head with a direct injection system plus restyled combustion chambers. Like K20C1, it’s supplied with a lightweight crankshaft plus restyled pistons with a compression rate of 10.8. Output is 158 horsepower at 6,500 rpm and torque is 187 Nm at 4,200 rpm.
13. K20C3 is analogous to K20C1, but it employs an MHI TD03 turbocharger, reaching a compression index of 10.8. Output is 272 horsepower at 6,500 rpm while torque is 370 Nm at 1,500-4,000 rpm.
14. K20C4 is another version of K20C1, keeping an MHI TD03 turbocharger, and having a boost pressure of 20.8 psi (1.43 bar). It reaches 252 horsepower at 6,500 rpm with a torque of 370 Nm at 1,500-4,000 rpm.

Honda K20A Engine

Honda initiated the production of K20, a 4-cylinder 4-stroke motor, in 2001. Steering clear of old traditional timings employs computer ignition timings, contributing to the vehicle’s better start and more efficient handling. Honda planned to substitute the B-range motors with K engines, which have a more efficient design, an advanced Valvetrain, and an improved build quality.

K20 motor features a clockwise rotation in its construction.

Until K20 was presented, all Honda motors kept a counterclockwise rotation. The brand worked pretty hard to make its motors meet contemporary demands, reducing emissions and achieving better reliability and durability.

Honda K20A (K20Z, K20C) Engine Problems And Reliability

1. Rattling noise in the motor. It’s a sign that it’s necessary to regulate valves. Otherwise, you may face quick wear out of the exhaust camshaft. This malfunction is pretty typical for K20 motors. Camshaft must be examined and substituted if it’s spoilt. Quick or extreme wear out of the camshaft is the consequence of an improper change of the motor oil plus application of bad quality oil.
2. Oil Leakage. Have a look at the crankshaft front gasket. Usually, the substitution of the seal fixes this trouble.
3. Rough idle. Mostly, the malfunction is solved by cleaning the throttle body or the idle air control valve.
4. Excessive vibration. This trouble is usually induced by motor mounts. Worn-out motors may also face troubles with a stretched timing chain. Moreover, motors released in 2000-2003 frequently face overheating of the fourth cylinder. Ultimately, K20 is a durable motor, which may have a pretty long lifespan if to apply proper oil plus high-quality fuel. It’s also important to follow the manufacturer’s instructions and serve the motor on time. Thus, your K20 will be able to run more than 200,000 miles with no trouble.

The information provided in this article is for general informational purposes only. The author and publisher make no representations or warranties of any kind, express or implied, regarding the accuracy, adequacy, validity, reliability, availability, or completeness of any information presented. The reader is advised to consult a qualified professional, such as a mechanic or dealership, before making any decisions related to their vehicle's engine oil or maintenance.