The Mitsubishi 3B21T 1.0-liter 3-cylinder turbo engine was produced from 2006 to 2014 and was installed on advanced versions of the second generation of the Smart Fortwo model in the back of the W451. The usual modification of this unit developed 84 hp, and in the version from Brabus from 98 to 102 hp.
3B2 family: 3B20, 3B20T, 3B21, 3B21T.
Specifications
| Production years | 2006-2014 |
| Displacement, cc | 999 |
| Fuel system | distributed injection |
| Power output, hp | 84 – 102 |
| Torque output, Nm | 120 – 147 |
| Cylinder block | aluminum R3 |
| Block head | aluminum 12v |
| Cylinder bore, mm | 72 |
| Piston stroke, mm | 81.8 |
| Compression ratio | 10.0 |
| Features | DOHC |
| Hydraulic lifters | no |
| Timing drive | chain |
| Phase regulator | MIVEC |
| Turbocharging | MHI TD025M1 |
| Recommended engine oil | 5W-30 |
| Engine oil capacity, liter | 3.4 |
| Fuel type | petrol |
| Euro standards | EURO 4/5 |
| Fuel consumption, L/100 km (for Smart Fortwo 2012) — city — highway — combined |
6.4 4.1 4.9 |
| Engine lifespan, km | ~200 000 |
| Weight, kg | 69 (without attachments) |
The engine was installed on:
- Smart Fortwo 2 (W451) in 2006 – 2014.
Disadvantages of the Mitsubishi 3B21T engine
- This power unit is quite reliable for a turbo engine, but its consumption is too high;
- The main thing is to monitor the cooling system; in case of overheating, it immediately leads the head of the block;
- Due to hardened o-rings, grease often pours into candle wells;
- Closer to 150,000 km, the turbine or timing chain may already require attention;
- Since there are no hydraulic lifters, the valves need to be adjusted every 100,000 km.
Frequently asked questions about the Mitsubishi 3B21T
How much power does the Mitsubishi 3B21T make?
The Mitsubishi 3B21T develops 84 - 102 hp and 120 - 147 Nm of torque.
How much oil does the Mitsubishi 3B21T take and which one?
Engine oil capacity: 3.4 liters. Recommended oil: 5W-30.
Does the Mitsubishi 3B21T have a timing belt or chain?
The Mitsubishi 3B21T uses a timing chain.
Is the Mitsubishi 3B21T turbocharged?
Yes, the Mitsubishi 3B21T is turbocharged (MHI TD025M1).
Does the Mitsubishi 3B21T need valve clearance adjustment?
Yes, there are no hydraulic lifters, so the valve clearances have to be checked and adjusted periodically.
How long does the Mitsubishi 3B21T last?
The typical lifespan of the Mitsubishi 3B21T is ~200 000 km with proper maintenance.
What is the fuel consumption of the Mitsubishi 3B21T?
Smart Fortwo 2012: city 6.4, highway 4.1, combined 4.9 L/100 km.
What cars was the Mitsubishi 3B21T installed on?
Smart Fortwo 2 (W451) in 2006 - 2014.
What are the common problems of the Mitsubishi 3B21T?
This power unit is quite reliable for a turbo engine, but its consumption is too high. The main thing is to monitor the cooling system; in case of overheating, it immediately leads the head of the block. All known problems.
