Getting the ECU to fire the coils from the crank sensor is the first step in getting the engine running, and usually the easiest to diagnose and fix.

Firstly, with the ECU connected to the MIETE, we need to create a quick ‘Diagnostics Tab’. Add a new tab in the usual way, and add to it the following widgets:

-Engine RPM
-Sync Status
-Lost Sync Count
-CAM IRQs
-CRANK IRQs

Check that the Trigger Types for the crank and cam are set correctly under the “System>Engine Driver”.

Disconnect the injectors and the coils, and then crank the engine.

Firstly, check that the ECU does not ‘power off’ while cranking. This could be either low voltage (in which case you need better grounding, power connections or a stronger battery), or incorrect wiring to the key barrel.

The first thing you should see are the Crank IRQs and, if being used CAM IRQs increase at a steady rate. This means your sensor(s) are OK  (it may be noisy) but it at least shows that the ECU is picking up engine ‘motion’.

We will assume you still don’t have an RPM yet, (if you did and all wiring for the coils and coil rest states are correct then they should indeed be sparking!), so have a look at the Sync Status readout. A status of 0 means that not even crank sync occurred, whereas a state of HALF means crank sync, but the EXPECTED cam sync was not found (note the ECU does not check for CAM sync if not using a CAM sensor, and wil go straight to ‘2’ if crank sync is found). A state of ‘FULL’ means that full sync occurred, and the coils SHOULD be firing, unless, the LOST SYNC count is also steadily increasing, which means that it is getting Sync, then losing it.

This could be down to incorrect cam/crank trigger settings, OR noisy signal lines. Check you have shielded cable for the cam/crank lines, and that the shields are earthed at the ECU end ONLY. Also check there is no ‘run-out’ or oscillation of any aftermarket trigger wheel, and that the gap is around 0.5-3mm from the sensor to the teeth.

If the system gets a nice steady RPM while cranking with the coils unplugged, but loses it once you plug in the coils, this is HT noise entering the crank triggering wiring - shield where appropriate.

Also, try swapping the cam +/- wires or crank +/- as if these are wired inverted it can cause issues also.

With all of the above correctly set, and the sensor correctly wired (refer to the hardware installation section) then the RPM reading should go live and read 100-300rpm while cranking. If it does not, please get in touch via a support ticket on our website.

There is a further option of removing background electrical noise using User settable trigger levels.