VehicleFitment/Toyota/Triggers (2015-01-01 07:00:00)

4A-GE Trigger

The connector is described at 4A-GEPinOut

02476 261824 Ex CTR

These have a potential market for Corolla (AE86 and newer) and MR2. These engines are used in Mk1&Mk2 Ford Escorts as they are very similar to the Cosworth BDA engine, powerful and light.

Some decent scope traces.

http://www.jamesmccombe.com/tube/Cars/MR2/ImageLibrary/Thumbnails/Drivetrain/EngineManagement/DistributorTesting/ContactSheet.shtml

Information on the Toyota 4A-GE timing system - distributor driven.

http://www.autoshop101.com/forms/h23.pdf


An attempt was made to use the G1 trigger using a simple trigger configuration. The problem is that the trigger teeth are 0 or 180 degrees (depending on how you look at things) advanced from TDC.

Toyota4AEGSignals.gif

I think that the correct way to trigger from this setup will be to use the 12 tooth NE trigger as the primary, and reset on each G1 pulse we will then be able to trigger from a specific NE tooth

Note, with this system it is impossible to determine which cylinder is firing so the injection is done simulataneously and the spark is distributed via a mechanical distributor. By considering the G signal as a reset and 1/4 of the trigger wheel you could run it with 1 spark and batch ignition firing all injectors at the same time. This would work for a plug and play application. Alternatively switch the wheel out from a later trigger unit with 1 G pulse.

Later Trigger types

Toyota have developed sensors for their later engines (such as found on MembersPage/DanielHenriksson page). These use either a single tooth G trigger:

Toyota4AEGSingleHome.gif

Or a twin tooth G trigger:

Toyota4AEGTwinHome.gif