Engine Overview and Common Failures
The weight of the 1AZ-FSE engine according to the catalog is 135 kg. The engine number 1AZ-FSE is located at the junction of the block and the gearbox. Owners of AZ series engines often encountered oil and antifreeze mixing. The short-threaded head bolts were to blame for this, as they couldn't withstand the load. The manufacturer increased the thread length in 2006 and this problem practically disappeared. Quirks of the injection system. The D4 second-generation direct injection system is used here, which is more reliable than the first one, but it has the same requirements for fuel quality or filter replacement frequency. Also, this engine is prone to spontaneous vibrations when any sensor fails. Oil consumption due to clogged oil rings usually appears at 100,000 km. By the way, updated engines after 2006 suffer from oil consumption more often. Low timing chain life. Single-row timing chain and phasing system often fail at 150,000 km mileage. Cold cracking, jerking, errors in valve timing failures occur. Minor breakdowns. Weak points of this unit include the water pump, generator freewheel clutch, and also the EGR valve, which causes this engine to quickly accumulate carbon deposits. On early-year engines, the plastic intake manifold vibrated at low RPMs. There are no hydraulic compensators and the valve clearances are adjusted by selecting pushers.