Mitsubishi 4G15

Mitsubishi 4G15 engine

  1. Specifications
  2. Overview, problems
  3. Performance tuning


Manufacturer Mizushima plant
Also called Orion
Production 1989-present
Cylinder block alloy Cast-iron
Configuration Inline-4
Valvetrain SOHC
2 valves per cylinder
3 valves per cylinder
4 valves per cylinder
4 valves per cylinder
Piston stroke, mm (inch) 82 (3.23)
Cylinder bore, mm (inch) 75.5 (2.97)
Compression ratio 9.0
Displacement 1468 cc (89.6 cu in)
Power output 64 kW (88 HP) at 5,750 rpm
68 kW (92 HP) at 6,000 rpm
72 kW (98 HP) at 6,000 rpm
76 kW (103 HP) at 6,000 rpm
77 kW (105 HP) at 6,000 rpm
79 kW (107 HP) at 6,000 rpm
87 kW (118 HP) at 6,000 rpm
108 kW (147 HP) at 6,000 rpm (Ralliart)
113 kW (154 HP) at 6,000 rpm (Ralliart)
113 kW (154 HP) at 6,000 rpm (Ralliart)
120 kW (163 HP) at 6,000 rpm (Version R)
132 kW (180 HP) at 6,000 rpm (CZT Ralliart)
Torque output 114 Nm (84 lb·ft) at 2,750 rpm
126 Nm (93 lb·ft) at 3,000 rpm
135 Nm (100 lb·ft) at 4,500 rpm
130 Nm (96 lb·ft) at 4,500 rpm
134 Nm (99 lb·ft) at 5,000 rpm
134 Nm (99 lb·ft) at 3,000 rpm
150 Nm (111 lb·ft) at 3,000 rpm
210 Nm (155 lb·ft) at 3,500 rpm
210 Nm (155 lb·ft) at 3,500 rpm
180 Nm (133 lb·ft) at 2,500 rpm (CVT)
210 Nm (155 lb·ft) at 3,500 rpm
245 Nm (181 lb·ft) at 3,500 rpm
Redline 6,500 (Ralliart)
HP per liter 60
Fuel type Gasoline
Weight, kg (lbs) 115 (254) – NA
126 (278) – Turbo
Fuel consumption, L/100 km (mpg)

Mitsubishi Colt Ralliart
8.5 (27.7)
5.5 (42.8)

6.6 (35.6)
Turbocharger  Naturally aspirated
MHI TF035HM-10T-5
Oil consumption , L/1000 km
(qt. per miles)
up to 1.0
(1 qt. per 600 miles)
Recommended engine oil 5W-20
10W-30 (Turbo)
Engine oil capacity, L (qt.) 3.3 (3.5) – NA
3.7 (3.9) – Turbo
Oil change interval, km (miles) 5,000-10,000
Normal engine operating temperature, °C (F)
Engine lifespan, km (miles)
-Official information

250,000 – 300,000 (150,000 – 180,000)
Tuning, HP
-Max HP
-No life span loss


The engine is installed in Mitsubishi Colt Ralliart
Mitsubishi Lancer
Mitsubishi Mirage
Mitsubishi Dingo
Mitsubishi Maven
Dodge Colt
Eagle Summit
Hyundai Excel
Proton Saga
Proton Satria
Smart Forfour
Brilliance BS2
Changan CS35
Emgrand EC7
Haval H1
Haval H2
Haval H6/Haval H6 Sport
Haval H6 Coupe
Geely MK
Geely Yuanjing X3
Great Wall Cowry
Great Wall Florid
Great Wall Voleex C30
Great Wall Voleex C50
Yusheng S330
Zotye T600

Mitsubishi 4G15 engine reliability, problems and repair

For the first time, this engine was installed in 1989 in the Mitsubishi Mirage, where it replaced the old G15B engine. This engine uses the same 4G13 cylinder block, its height is 201 mm, but they increased the cylinder bore from 71 mm to 75.5 mm. This provided an opportunity to obtain the displacement of 1.5 liters.

On top of the cylinder block, there was a 12-valve SOHC cylinder head with 3 valves per cylinder (2 intake and 1 exhaust valve). The diameter of the intake valve was 26 mm, of the exhaust valve — 33 mm, the valve stem thickness was 6.6 mm.
The compression ratio of such an engine is 9.2; either a carburetor fuel system or a single-point fuel injection are used here.
The power of a 12 valve 4G15 SOHC is 90 HP at 6,000 rpm, the torque of 122 Nm at 3,000 rpm. Since 1995, the 16 valve DOHC head with 4 valves per cylinder has been used. It had a camshaft with a duration of 235/241 deg. This cylinder head does not have hydraulic lifters, therefore, valves should be adjusted approximately after every 60,000 miles (100,000 km). Usually, no one does it, and the engine is used until the ticking noise appears. For a hot engine, valve clearances are as follows: intake valves — 0.15 mm, exhaust valves — 0.25 mm. For a cold engine, the clearances for intake valves are 0.07 mm, for exhaust valves — 0.17 mm. A timing belt with a service life of about 60,000 miles (100,000 km) is used here. When it breaks off, the valves will bend.
The firing order is 1-3-4-2. Besides, the multi-point fuel injection system was used in these engines.
Such 4G15 DOHC showed 110 HP at 6,000 rpm and the torque of 137 Nm at 3,000 rpm.

From 1998 to 2002 a modification with direct fuel injection was produced, which was called 4G15 GDI. This allowed obtaining 100 HP at 6,000 rpm and the torque of 140 Nm at 3,000 rpm.

Between 2001 and 2009, version 4G15 with a 16 valve SOHC head was produced, its power was 90 HP at 5,250 rpm, the torque of 133 Nm at 3,750 rpm.

In 2002 – 2004, one could buy a car with a 4G15 engine, where the MIVEC DOHC head was used. It developed 98 HP at 6,000 rpm, the torque of 132 Nm at 4,250 rpm.

In 2004, a top-end turbocharged 4G15 engine with the MIVEC system was introduced. It was intended for sports models and had a cylinder block with oil squirters and a lower compression ratio — 9.0. Here the TF035HM-10T-5 turbocharger with an intercooler was used with the boost pressure of 8.7 psi (0.6 bar). For a more powerful engine, the engineers used a 305 cc/min fuel injector. This resulted in an engine with 154 HP at 6,000 rpm and a torque of 210 Nm at 3,500 rpm. For the cars with the CVT transmission,
the torque is limited to 180 Nm at 2,500 rpm.
Later the power was increased to 163 HP at 6,000 rpm, and then to 180 HP at 6,000 rpm and the torque increased to 245 Nm at 3,500 rpm.

Want such an engine? Buy a Mitsubishi Colt Ralliart or a Smart Forfour Brabus. Yes, it was installed into the Smart, and there it is designated as Mercedes M122 E15 AL.

The Mitsubishi Company has developed other engines using 4G15, and they formed the Orion family. These were 4G13, 4G18, and other engines popular worldwide.
Replacement of the 4A91 with the 4G15 engine continued from 2004 to 2012, after which the 4G15 was removed from the main lineup of Mitsubishi cars, but can be found in cars from other manufacturers.

Mitsubishi 4G15 engine problems and malfunctions

1. Rough idle. High idle or rough idle is normal for the Mitsubishi 4G1 engines. The reason is the throttle body, it is usually the case. It is probably worn out and needs replacement.
2. Vibrations. They happen quite often in all 4G1 engines, but the reasons may be different. Check the state of engine mounts, the problem is likely to be in them. Sometimes the problem is solved by slightly increasing the idle.
3. The engine won’t start. Check the fuel pump first, but if you live the environment with heavy frosts, check the spark plugs, the problem will be there. These engines do not tolerate frost.
4. High oil consumption. This is a common problem for an old engine with the mileage over 120,000 miles, and for 4G18 even 60,000+ miles is enough. In such cases, the piston rings are replaced and the engine is used on, but it is not reliable and not for a long time. A good overhaul is better.

Summing up, it is a good, fairly reliable engine, but sometimes it may get you into trouble. Regularly perform maintenance, and use good motor oil.
Want to buy a car with a 4G15? Pay attention to other engines, for example, for a Mitsubishi Lancer, it is better to choose the 4G63, it is much better quality and more reliable engine.

Engine number location

Look for it under the exhaust manifold on the right.

Mitsubishi 4G15 engine tuning

Naturally aspirated

There are two ways how to make 4G15 faster: naturally aspirated and forced induction. The first variant is a waste of money, and you won’t get anything except for a loud exhaust, but you can try it. Install an aftermarket air filter, 60 mm throttle body, 4-2-1 header, 2-inch exhaust system, and tune your ECU. These performance mods will improve the sound and will add 15 to 20 horsepower. You can spend more money and install an additional ITB (or performance intake manifold), high compression pistons, aftermarket cams 270/275 deg, adjustable cam gears, do port and polish, install new spark plugs, lightweight flywheel and configure all this. I doubt that it is a reasonable investment, but the car will get a little more power.


Let’s see what upgrades you will need to make a 4G15 turbo. At eBay, find an appropriate turbo kit and buy a turbo manifold, TF035 turbocharger (or something similar), oil feed line, oil drain line and put it all on stock internals. You will also need an intercooler, a turbo piping kit, 4G64 fuel injectors 275 cc (or more), a Walbro 255 lph fuel pump, a 2.5-inch exhaust system, a wideband O2 sensor, and Greddy E-Manage. Stock internals are pretty weak, but they will survive the pressure up to 7 psi, and you will be able to drive a little in this mode. However, it is better to do everything properly.
Dispose of stock pistons and stock connecting rods, as they are good for nothing. Buy forged low compression pistons (compression ratio ~8.5), H-beam rods, ARP head studs, and an MLS head gasket. I also recommend installing oil jets for piston cooling. You will need a big Mishimoto radiator, a big intercooler, an oil cooler, a fuel rail, 630 cc fuel injectors, a fuel pressure regulator, and a blow-off valve. To gain more power you will need a large TD05 turbocharger (Evo turbo) or another one of similar size. Using such performance parts, you may get up to 350 horsepower. Still want more? Then you need an aftermarket crankshaft because the stock crankshaft cannot withstand high power. It is also better to use DOHC 16-valve cylinder head for turbo, it will improve efficiency.