Megasquirt problems
 

I tried to install my megasquirt today. I got everything together and went to fire it with no luck. I am not getting a tach signal to the dash or megasquirt when I am trying to start it...is that a problem? I am running a parallel setup. It will just keep turning over but never fire.

I now have a sig to tell about my car.

Figure out why you arent getting a tach signal. Did you properly assemble the tach input circuit for the miata?

I bought it used from a known working miata. I also tried to use a spare igniter I had here and nothing changed.

What year miata was it built for? 90-93 94-97 99+ all have different pin outs for the same ECU connector. Have quick look at brains DIY HOWTO and see if you can work your harness out. Also if you are running parrallel try running the car on the OEM ECU with just the MS sensors connected so you can troubleshoot your inputs.

Forget the dash tach for the moment. If you're not getting a tach indication on the MS, that's probably root cause.

The dash tach is fed by the igniter, however the igniter is fed by the MS. Ergo, ignore the igniter right now.

The MS displays a tach indication based upon the signals it receives from the CAS, namely CKP and CMP. So that's where you start. Make sure that the MS is internally modified to take in CKP and CMP on pins 24 and 25, and that pin 25 is configured to drive pin 11 of the CPU. Instructions: How to MegaSquirt your Mazda Miata

Then, verify that they're connected to the right wires at the ECU harness. Normally I'd infer that you have a '90-'93 from the mention of a separate igniter, though I don't know whether the UK cars kept the igniter on later 1.6s or not.