Toyota 1MZ-FE Engine Specs, Problems And Reliability

Engine 1MZ-FE – it’s the middle brother in the line, its cylinder capacity is about 3.0 liters (2994 cc.).

Bore and stroke of 87.5 mm and 83 mm, respectively. Power output varies from model year and the availability of variable valve timing system VVT-i and is in the range of 168-210 hp at 5200-5400 rpm and of 290-300 Nm at 4400 rpm. The 1MZ-FE engine has a high fuel efficiency without high losses of power.

Later, the gas distribution system of engine 1MZ-FE was complemented with the VVTi variable valve timing system.

The capacity of such a motor makes 210 hp at 5800 rpm and a torque of 328 Nm at 4400 rpm. Early versions of the engine 1MZ-FE with VVT-i system staffed throttle double hull, cast aluminum intake manifold, and EGR system. In later versions of the engine installed plastic intake manifold to reduce weight and further reduce the cost. Optionally, they manned the throttle with electronic control.

This engine’s firing order is 1–2–3–4–5–6. The cylinder head is made of aluminum alloy, with a cross-flow type intake and exhaust layout and with pent–roof type combustion chambers. The spark plugs are located in the center of the combustion chambers. At the front and rear of the intake manifold, a water passage has been provided which connects the RH and LH cylinder heads.

Exhaust and intake valves are equipped with irregular pitch springs made of special valve spring carbon steel which are capable of following the cam profile at all engine speeds. The RH and LH exhaust camshafts are driven by a single timing belt, and a gear on the exhaust camshaft engages with a gear on the intake camshaft to drive it.

The camshaft journal is supported at 5 places between the valve lifters of each cylinder and on the front end of the cylinder head. Lubrication of the cam journals and gears is accomplished by oil being supplied through the oiler port in the center of the camshaft.

Adjustment of the valve clearance is done by means of an outer shim type system, in which valve adjusting shims are located above the valve lifters. This permits the replacement of the shims without the removal of the camshafts. The timing belt covers consist of resin type No.2 and No.1 above and below the engine RH mounting bracket.

Pistons are made of high temperature–resistant aluminum alloy, and depression is built into the piston head to prevent interference with the valves. Piston pins are the full–floating type, with the pins fastened to neither the piston boss nor the connecting rods. Instead, snap rings are fitted on both ends of the pins, preventing the pins from falling out.

The No.1 compression ring is made of steel and the No.2 compression ring is made of cast iron. The oil ring also is made of a combination of steel and stainless steel. The outer diameter of each piston ring is slightly larger than the diameter of the piston and the flexibility of the rings allows them to hug the cylinder walls when they are mounted on the piston. Compression rings No. 1 and No.2 work to prevent gas leakage from the cylinder and the oil ring works to clear oil off the cylinder walls to prevent it from entering the combustion chambers.

In 1996, he was in the top ten best engines of the year published by the American magazine Ward’s.

1MZ-FE Engine Specs

What Cars Have A Toyota 1MZ-FE?

• 1993–2006 Toyota Camry (V6)
• 1993–2003 Lexus ES 300 & Toyota Windom (Japanese domestic market)
• 1994–2004 Toyota Avalon & 2000 Toyota Pronard (Avalon for Japanese domestic market)
• Toyota Harrier (non-US markets)
• 1997–2000 Toyota Sienna
• 04.1997–12.2001 Toyota Mark II Wagon (Japanese domestic market)
• 1998–2003 Toyota Solara (V6)
• 2000–2005 Toyota Estima (Japanese domestic market)

Toyota 1MZ-FE Engine Coolant Capacity

1. CHECK ENGINE COOLANT LEVEL AT RESERVOIR TANK

The engine coolant level should be between the ”LOW” and ”FULL” lines. If low, check for leaks and add engine coolant up to the ”FULL” line.

2. CHECK ENGINE COOLANT QUALITY

(a) Remove the radiator cap from the water outlet.

CAUTION: To avoid the danger of being burned, do not remove the radiator cap while the engine and radiator are still hot, as fluid and steam can be blown out under pressure.

(b) There should not be any excessive deposits of rust or scale around the radiator cap or water outlet filler hole, and the coolant should be free from oil.

If excessively dirty, clean the coolant passages and replace the coolant.

HINT:

• Use a good brand of ethylene–glycol base coolant and mix it according to the manufacturer’s directions.
• Using coolant which includes more than 50 % ethylene–glycol (but not more than 70 %) is recommended.

NOTICE:

• Do not use an alcohol-type coolant. The coolant should be mixed with demineralized water or distilled water.

1MZ-FE Generator drive belt inspection

INSPECT DRIVE BELT

(a) Visually check the belt for excessive wear, frayed cords, etc. If necessary, replace the drive belt.

HINT: Cracks on the rib side of a belt are considered acceptable. If the belt has chunks missing from the ribs, it should be replaced.

(b) Measure the drive belt tension using a belt tension gauge.

Belt tension gauge:

• Nippondenso BTG – 20 (95506–00020)
• Burroughs No. BT–33–73F

Drive belt tension:

• New belt: 175 ± 5 lbf
• Used belt: 115 ±20 lbf

If the belt tension is not as specified, adjust it.

HINT:

• ”New belt” refers to a belt that has been used less than 5 minutes on a running engine.
• ”Used belt” refers to a belt that has been used on a running engine for 5 minutes or more.
• After installing the belt, check that it fits properly in the ribbed grooves.
• Check by hand to confirm that the belt has not slipped out of the groove on the bottom of the pulley.
• After installing a new belt, run the engine for about 5 minutes and recheck the belt tension.

1MZ-FE Engine Problems and Reliability

During operation, the 1MZ FE motor is susceptible to certain “diseases” due to its design features.

Cast iron valve sleeves used in the block are not repairable, so everything except the cylinder block can be replaced.