So according to Wikipedia there are several iterations of the 4D56...

There's the Turbo Non-intercooled with the distributor type injection pump.

There's the Turbo with Intercooler, still with distributor type injection pump.

Then there's the Common Rail Direct Injection.

I need to know the years and models for cutoffs for the middle one. I do not want to deal with the electronics required for Common rail injection. Yet, I want a later slightly more powerful engine designed to be used with an intercooler.

Or are there any differences between the first two? I am going to be using an aftermarket intercooler, so I don't NEED the stocker. I just thought that perhaps the one originally intercooled would be a better, later model engine.

Common Rail 4D56 engines only come in the new Mitsu L200 Pickup (2005-2006), and it is a very different engine than the old one.

From around '95 the 4D56 got an ECU, depending on country/region and vehicle. Around '98 there was a minor head/piston redesign.

Any turbo engine can benefit from an intercooler. The only difference between the 4D56 engines that come with intercooler from the factory is that the pump lets a little more fuel in to account for the increase in air, but that's about it.

An ECU for a diesel engine? What does it control and how?

Don't know how it works, but the ECUs on non common rail diesels are very simple. They are supposed to give better fuel efficiency and increase power a little bit. The fuel pump of an ECU controlled 4D56 and a plain one seem almost identical to me, but the ECU controlled has a couple of sensors and wires attached.

Works pretty much just like a gasoline injected engine, except no spark control. Replaces the distributor style injector with electronic injectors fed from a common high pressure fuel rail. ECU controls timing and amount of fuel to inject based on different input sensors.

Would this not be a "common rail" diesel?

I thought it was said that there was a diesel engine with a distributor type injection pump and ECU at the same time. This didn't add up with me.

Mitsubishu has developed various types of turbo diesel engines:

1. Injector Pump with mechanical control (eg early versions of the 4d56 and 4m40 engines).
These diesel engines have mechanical injector pumps with no compensation controls.
This means that the throttle acts as a "tap", opening a valve which allows more diesel to be fed to the injectors.
Once the calibration and pump timing is set, the diesel delivery is controlled by throttle setting only.
The only compensation is for high boost situations. The pump has a vacuum valve, activated by boost pressure, that allows more diesel at high boost.


2. Mechanical pumps with electronic control (ECU) (eg later versions of the 4d56 and 4m40 engines, as well as the 4m41 3.2 Di-D engine)
These engines still have mechanical injection pumps, but the timing and volume of the diesel injection is controlled by sensors and a ECU.


3. Common Rail diesel engines (eg the 2007 versions of the 4d56 and the 4m41. The 4m40 seems to have been discontinued)
These engines have no injector pump, but a high pressure pump, that keeps a common rail (manifold) under extremely high pressure.
The timing and volume of the diesel injection is controlled by ECU and sensors. The ECU controls the feed of diesel fuel from the common rail (manifold) to the injectors according to the mapping of the ECU, the sensors, temp, load, speed etc.

The down side of the Common Rail engine is the reliance on very clean diesel fuel. The pressures in the manifold and injectors are similar to those in liquid cutting equipment. Any impurities will erode the injectors very quickly)

You would think that a good fuel filter would take care of that..

EXCELLENT! That's the stuff I'm looking for.

Any clue on the years the Mechanical and electronics control injection pumps were introduced?

I thought the 4D56 was discontinued entirely. What's the 2007 version used in?

Think the ECU controlled mechanical version has a limp home mode so that it'd run without the ECU. Maybe base timing and fuel. I wonder how complex that ECU is to hook up.

Mitsu introduced various engines in various models in various countries, so it would be risky to try and list them here. Somebody else might know, but I don't.


It is used in the Triton SUV (L200), which was launched in Australia a while back and just recently here is South Africa.


It look us months and the original 700 page Mitsu manual to figure out the 4m41's wiring and peripherals. (I have a 4m41 in my Gen1)
Without the manual and electronic know-how I think it would be impossible.



The exiting model will be the 3,2 DiD Common Rail:
http://www.gethard.co.nz/