Toyota introduced the 1MZ-FE in 1993 as an engine for their larger sedans which needed more power than a four-cylinder could supply at the time. It was designed to replace the very outdated VZ engine family. It’s been entirely phased out and replaced by the GR engine family which is much more efficient and powerful, but the 1MZ-FE is still a pretty good little engine. Although it doesn’t have the cult following the 1UZ or 2JZ has, it’s still a very popular engine. In this short guide, we’re going to dive into the 1MZ-FE and tell you everything you need to know. You can also find even more information on Toyota MZ Wikipedia page.
1MZ-FE: Engine Basics and Specs
The 1MZ-FE uses a closed deck V6 design with an aluminum cylinder block and aluminum cylinder heads. Part of the reason Toyota went to an all aluminum design is to decrease total engine weight. Toyota also used a very lightweight rotating assembly in hopes of creating a smoother and more efficient engine. The heads use a DOHC camshaft design with 4-valves per cylinder with Toyota’s basic multiport fuel injection system.
This engine features a forged steel crankshaft, one piece camshafts, a cast aluminum intake manifold, and later version received Toyota’s VVT-i system. Earlier engines without VVT-i used cast aluminum pistons with cutouts to decrease the chance of piston to valve interference if the timing belt were to break. Some versions of this engine featured a bolt-on TRD supercharger kit which majorly increased horsepower and torque.
- Production Run: 1993 – 2007
- Displacement: 2994cc
- Cylinder Block Material: Aluminum
- Cylinder Head Material: Aluminum
- Valvetrain: Dual Over Head Cams – Four Valve per Cylinder
- Stroke: 83mm
- Bore: 87.5mm
- Compression Ratio: 10.5:1
- Horsepower: 168hp to 242hp
- Torque: 183 lb-ft to 242 lb-ft
Cars That Came With the 1MZ-FE
Just like the 2AZ, 2GR, 1UZ, and many other Toyota engines, the 1MZ came in a variety of different vehicles over the years. Pretty much every single car the 1MZ was used in was a front wheel drive sedan. Toyota really spent a lot of time making sure the 1MZ was a very smooth running engine for the typical commuting that a sedan would be used for.
- 1993 – 2006: Toyota Camry
- 1993 – 2003: Lexus ES 300
- 1993 – 2003: Toyota Wisdom (JDM)
- 1994 – 2004 Toyota Avalon (JDM)
- 1997 – 2000: Toyota Sienna
- 1997 – 2001: Toyota Mark II Wagon (JDM)
- 1998 – 2003: Toyota Solara
- 2000 – 2005: Toyota Estima (JDM)
- 1998 – 2003: Lexus RX 300
- 2000 – 2003: Toyota Highlander
- 2002 – 2007: Toyota Alphrad (JDM)
1MZ-FE: Known Problems
Quite a few Toyota engines have been known for excessive oil consumption, but for the most part, Toyota makes very reliable engines. Part of this is because they don’t really push the envelope in terms of performance which results in very long lasting engines. There are two well-known and somewhat common issues with the 1MZ-FE.
The first issue is overly sensitive knock sensors. The job of the knock sensor is to detect any knock that could come from things like detonation. If a knock is detected that is outside the normal range the computer will decrease ignition timing which decreases power. Unfortunately, the knock sensor on the 1MZ is far too sensitive and reports of the ECU randomly pulling power are very common.
The second issue has to do with how quickly the oil reaches operating temperatures. This occurs when you commute very short drives regularly. This can cause a buildup of oil sludge when can be detrimental to your engine. Part of this issue also comes up from regular oil change intervals being ignored.
1MZ-FE: Tuning Potential
Unlike the 1UZ, 1JZ, or 2JZ, the 1MZ isn’t really an engine that people modify. This is mostly because it didn’t come in any performance oriented cars and the majority of owners just want a reliable commuter.
Arguably the best modification you can do to a 1MZ-FE is adding a TRD supercharger. In the case of the Camry, Sienna, and Solara the addition of a supercharger bumps the power up to 242 hp and 242 lb-ft. If you’re interested in doing a naturally aspirated build the best option is just simple bolt-ons like an intake and exhaust.
If you really want to squeeze as much power out of the 1MZ as possible you can port and polish the cylinder heads. If you really want power you’ll need to upgrade to a different Toyota engine. The 1MZ-FE is really not at all meant for any kind of high horsepower usage and you’ll have better luck with a 2GR-FE.
Although this article is focused on the 1MZ-FE, we felt it would be a nice addition if we touched on the 2MZ and 3MZ version. The 2MZ-FE retains many of the technologies used in the 1MZ-FE, but with a smaller displacement. The 2MZ-FE retains the same 87.5mm bore that the 1MZ uses, but stroke is decreased to a tiny 69.2mm. This lowers the displacement from 3.0L down to 2.5L. This engine was used in a few different vehicles all of which were not available in the US.
Like the 2MZ, the 3MZ-FE retains all the technologies of the 1MZ-FE and adds some of its own. Unlike the 2MZ, the 3MZ actually has a larger displacement than the 1MZ-FE. The 3MZ retains the same 83mm stroke as the 1MZ, but the bore is increased to a whopping 92mm. This increases the displacement up to 3.3L. In theory, the 3MZ should be very happy to rev thanks to its overbore design.
The biggest improvement in the 3MZ is a revised knock sensing system. As we mentioned above the extremely sensitive knock sensors were a large issue on the 1MZ. The redesigned knock sensor system on the 3MZ completely fixes all of these issues.