Fixing those things did NOT help.... Today though the car did buck/hesitate, then died while taking a turn, then picked back up. I heard a click, similar to a relay under the dash when it died. AFR's went lean while bucking too. Makes sense it'd be the fuel relay like you said. I'll be ordering a second one soon. Hopefully, the current one isn't busted.

 

The fuel pump has been put on a separate relay. I also snagged a used CAS off a junk 1994 so I can swap mine out with that one when it dies. We shall see...

 

Welp, those things did not help. Currently sitting on the side of the road... From what I can hear, the fuel pump relay clicks when I turn the key to the on position. The main relay seems to be working and is clean and not warped. No clue what's going on...

Edit: it's not the CAS, I plugged the "new" one in and spun the butterfly and nothing happened.

Edit: Cracked open the main relay.



Is it crooked? I dunno. I'll try and sand the terminal thingy down.

edit 3:


Cleaned up

 

I've had a main relay failure when it appeared to be making contact. You could hear it click when powered, but it just didn't power the car.
I always keep a spare CAS/Main Relay/Crank Position Sensor in the glovebox. That is great insurance against ever needing them in an emergency.
I've gone through a couple since adding my larger fuel pump, but am too lazy to rewire the fuel pump with its own relay since I have the spare in the glove box. I guess when it dies I'll rewire it.

 

When your relay failed, was it just dead and done? Or was it on and off like my situation?

 

I ******* figured out what it is. So tonight I was driving and I went over some bumps and the car cut out for a second. (To me at least) this screamed loose connection. I got home, pulled into the garage and the car died, wouldn't start. I started hitting **** and tugging on stuff. I hit my MS3X a couple of times and it fired right up.

Here's me doing a live test. I'll be cracking this thing open later tonight.
https://www.youtube.com/watch?v=FFGf...ature=youtu.be

 

Diode 24 cracked joint. I've gone in and resoldered some other stuff too. Hope this was the issue.

 

Put like 120 miles on the car since resoldering the pins. So far so good. I'm confident this was the fix. Thank you all for your help. All those recommendations yall have given me definitely saved me future headaches.

 

my car did this today. After about 30 min it started back up and I drove it home. I do have a walbro 190 LPH pump in it since larger pumps were mentioned earlier in this post.

im guessing I need to pull the computer and take a look for bad solder joints?

 

If you're on a megasquirt you built then I would consider it. I haven't heard of stock ecu's giving anyone trouble tbh. But if you can hit the ecu and the car cuts out, I'd say that's highly likely the cause lol.

 

Oof, this thread.

I have some experience with this as well. See: https://www.miataturbo.net/megasquir...-diypnp-68814/

All I can offer for advice is... good luck. Before you decide the ECU is the issue, make sure everything, and I mean EVERYTHING is perfect. Troubleshooting my bad solder joint issue was a nightmare, but my ECU harness wasn't hacked to pieces which made it much easier to isolate.

 

+1 for what EO2k said, make sure EVERYTHING is in order before delving into the ECU.

 

It’s on the stock ECU for the moment. I pulled and inspected it and all looked great. I recently installed an AEM wideband so I removed, cleaned and tightened the ground at the back of the block. I also swapped out the CAS. I’m placing the extra coil in the trunk just in case it stalls again. I’ll swap that and see what happens.