Teejay187

Hi,

I am having some issues where the engine stops turning while cranking.

I can see from the attached log that I am getting an sync error 31 quickly followed by a error 32 while cranking. Rpm jumps to around 2500 while cranking and ignition spikes to around 30. Seems like this is causing a backfire and it stops the engine from cranking.

I have attached a log from the startup, as well as the tune. I going getting a composite log tomorrow morning when the car has cooled down as I am not having issues on hot starts..

Battery voltage is dropping a lot just before the errors. Could this be due to a faulty starter? The battery is brand new!

BR,
Truls

Mech5700

https://www.miataturbo.net/megasquir...e-crank-80800/

Long story short, switch your rising/falling edge...

Teejay187

Will give it a try. Read that whole thread before posting, but read elsewhere that the MS2 should have Rising Edge.

Essential info: Stock 99 Miata, MS2E.

Mech5700

I don't think it is what the ecu "should have", but how the ecu reads the crank signal. Give it a shot and see, let us know!

Braineack

iTrader: (62)

It depends on the input circuit and decoder.

what exact MS model/variant do you have?

Teejay187

Reverant built MS2E. I haven't changed crank settings other than setting the offset.

Braineack

iTrader: (62)

you should ask him what's best for his unit. I'm assuming youll wanna keep it how it was setup to begin with.

Reverant

iTrader: (10)

Opto circuits. 90-97 = falling edge, 99-05 = rising edge.

Teejay187

Tried making some composite logs, seems like it stops logging sometimes while cranking. Anyway, I have made some progress. If I turn the key to the "on" position and let it sit for about 30-45 seconds before cranking, the chance of kickback is much lower.. Replacing the head this weekend, so I am going to clean the connectors at the same time, as well as checking grounds.

Teejay187

So back to this. Head replaced and removed A LOT of build up. Seemed a little better. Redid the cranking and pulse tables. All good now.