What can you tune on a Nissan ECU?

A Nissan ECU runs the engine from tables of numbers, usually called maps. Tuning means changing those numbers. Here's what the main ones do, so you know what you're looking at when you open your ECU in VQLab.

Ignition timing

How far before top dead centre the spark fires, by engine speed and load. More advance can make more power, until the engine starts to knock. Nissan ECUs usually have two timing maps, and move towards the safer one when they detect knock. Change timing in small steps and watch for knock.

Fuel target

The air-fuel ratio the ECU aims for at each speed and load. Richer (more fuel) is safer under load; leaner saves fuel when cruising. To tune fuel properly you need a wideband oxygen sensor to see what the engine actually gets.

Airflow (MAF) scaling

Converts the mass airflow sensor's voltage into how much air is entering the engine. It has to be right for everything else to be right, and it's the main thing to change after an intake or a different MAF housing.

Injector settings

Injector size and latency (how long an injector takes to open). Bigger injectors need these changed, or the engine will run rich.

Cam timing

On VQ engines with variable valve timing, how far the intake cams are advanced at each speed and load. It shapes where the engine makes its torque.

Limiters

Rev limits, speed limits and fuel cut. These are simple values, and often the first thing owners change. Know your engine's mechanical limits before raising a rev limit.

Pedal and throttle maps

On drive-by-wire cars, how much the throttle opens for each pedal position. Changing them changes how the car feels, not how much power it makes.

Before you change anything

• Back up your stock ECU first, and keep the file safe.
• Change one thing at a time, then log a drive and check the result.
• VQLab can scan a drive log with Claude, flag lean or rich spots and explain them, but every change is still yours to make.

See which maps VQLab knows for your car on the supported vehicles page.