Car died twice... starts a few hours later.
 

So I have a 99 miata, with diypnp I built myself.

About a month ago I was driving to work, lost all power and had 0 rpm. I pulled over, opened turner studio. Acting like I knew what I was looking at... I didn't see anything in the diagnostics tab with the ignition... Fuel pump was coming on, but injectors weren't firing, and had no spark. So I "checked" my cam sensor. (how does on actually check a cam sensor?) I had no 12v to it on any pins... weird. One of the wonderful benefits of working at a car dealership, we happen to have another 2000 miata. So I take my cam sensor with me. Put it in the other miata, and it started right up... Fast forward, I end up driving other miata home, as a parts car incase I need something. I jump in my car, starts right up.. Out of curiosity I check cam for 12 volts. It has 12 now. I took apart the ms, all my jumpers are okay, so I just try to forget about it.

TL;DR, randomly died, no fuel/spark. no 12volts to cam sensor. connect to m/s just fine. come back a few hours later and starts right up.

Then.. it happens again! I check the cam sensor again no 12 volts. No time to diagnose anything.. I shake ms, thinking a bad connection maybe nothing. So I leave it. come back 7 hours later, starts right up! AHHHHH:vash:. Why!

From wiring diagrams I've tried to lookup, the cam sensor gets its 12v from the ecu. If my ecu has power, then it might be a problem with the ms itself? Is there anything I can check on the ms that could be going bad?


tl;dr;tl;dr;tl;dr. died while driving twice, problem seems to be coming from no 12 volts to cam sensor. Megasquirt has power and connects to laptop. Leave car for a few hours, and starts when I come back.

If you help me I will give you :2cents::2cents::2cents:. Thanks!

Well yesterday morning on my way to work it died again.. so it seems like there is a common theme, when its wet, im stuck on the side of the road.

It took a while, but I finally got it home, driving very bad, like its loosing its cam signal. When I was home, it was running fine. So i start spraying the hose on it.. just a light mist. Everything seemed okay. I let it sit for a few minutes and it dies. Now its not starting at all. I'll be double checking everything tonight.. all connections, relays, such.

So whats the best way to check so see if cam sensor is giving a signal? I do not have a scope.. but I have tunerstudio! anything else I should check?

apparently those sensors fail when they get hot, and once they are bad will do it over and over...

Sounds to me like an IAT. getting too hot maybe.

just to update.

I bought a new cam sensor. I also bought a new diypnp... Seems to be running good now! I got a new ecu because I had some traces coming off where i burnt the board learning to solder. Also because I bought another 99 and want to try to fix that ecu and run it in the new miata!

New miata needs a new diff housing... anyone got one?

I was going to say fuel filter but looks like you got it handled. good for you. I hate when my car breaks down.