ECU

The ECU is the brain of your E30. It is responsible for controlling the operation of the engine

Overview

From the first carburetted M10 engines to the sophisticated M42, all E30s features some form of Engine Control Unit that operated some or all of the following features:

• Idle Speed
• Ignition
• Fuel Injection
• Fuel Mixture

The ECU and the system it managed changed incredibly from its first inception in 1982 to the final E30 in 1994. To understand them fully, it is necessary to know what system is fitted to your car

L-Jetronic

Main article: Jetronic

Motronic

Main article: Motronic

The Motronic ECU contains a fuel map with an injector opening time for basic conditions of speed and load. Information is then gathered from engine sensors such as the AFM, CPS, CTS, and TPS. As a result of this information, the ECU will look-up the correct injector pulse duration right across the engine rpm, load and temperature range.

List of ECUs

The following list shows which ECUs were fitted to which vehicles:

Table Title

ECU Number	System	Models	From/To
0260 200 005	Carburettor	316	1982-
0280 000 318	L-Jetronic	318i	1983 - 84
0280 000 330	L-Jetronic	318i	1984 - 87
0280 001 301	L-Jetronic	320i and 323i	1982 - 84
0280 001 309	L-Jetronic	Later 320i
0280 001 308	L-Jetronic	Later 323i
0280 000 310	L-Jetronic	Late 323i
0261 200 174	Motronic	316i	1988 Onwards
0261 200 157	Motronic	318i	1987 - 88
0261 200 175	Motronic	318iS	1989 onwards
0261 200 164	Motronic	325i Auto	9/87 onwards
0261 200 381	Motronic	320i	1987 onwards
0261 200 172	Motronic	320i	1987
0261 200 073	Motronic	325i Chrome bumper	1985 - 87
0261 200 173	Motronic	325i Plastic bumper	9/87 onwards
0261 200 380	Motronic	325i	8/88 onwards
0261 200 071	Motronic	Early 195/200bhp M3 and Evo 1
0261 200 090	Motronic	Evo II
0261 200 091	Motronic	M3 with 215bhp
0261 200 092	Motronic	Sport Evo
0261 200 042	Motronic	325e	until 9/85
0261 200087	Motronic	320iS
0261 200 074	Motronic	325e	9/85 onwards (Low compression)