Engine Overview and Common Failures
The weight of the 1NZ-FE engine according to the catalog is 92 kg. The engine number 1NZ-FE is located at the junction of the block and the cylinder head. The most well-known problem of this engine series is oil consumption after 100,000 km. There are many reasons for this: wear of oil control valve seals, piston ring sticking, clogging of crankcase ventilation. All culprits are listed in the Drive 2 blogs. The timing chain has a low lifespan. The timing mechanism uses a very thin roller chain with a pitch of only 8 mm, so its lifespan is naturally limited. Often, replacement is required before reaching 100,000 - 120,000 km. The VVT-i system lasts slightly longer and it is recommended to replace them simultaneously at service centers. This engine prefers good fuel and oil, otherwise it quickly becomes clogged with carbon deposits. Cleaning during fluctuating idle usually starts with the throttle body and ISCV valve, and if that doesn't help, then it's worth cleaning the MAF sensor and the crankcase ventilation valve. Oil leaks are common in all engines of this series, and they have weak points: oil seeps from the hydraulic tensioners, valve cover or rear crankshaft seal. There are also minor issues such as low durability of power unit supports, oil pressure sensor, and generator belt. Additionally, most versions of the engine do not have hydraulic lifters.