I just recieved word that my Hydra2.7 has melted part of its circuit board and is not firing one injector. This car was installed and tuned for me by a speed shop. The funny thing is that this is my second computer, (the first was a MS). Any ideas on what is causing this before I give the car a viking burial?

 

Are you using low-impedance (peak-n-hold) injectors?

Is this your second ECU because the MS also failed in this way, or was that just a random tidbit?


Also, welcome to MT. It's dangerous to go alone. Take this:

 

Hydra supports low impedance injectors.

--Ian

 

I was trying to figure out what kind of injectors that I have but they're somewhat hidden in the motor. They were purchased from BEGI along with with original Megasquirt PNP and the invoice just says "550cc injector for miata". Since the Megasquirt melted as well as I was looking for a potential installation error from the speed shop assuming BEGI sold me the right part. Does Megasquirt also require low impedance injectors or anyone know what BEGI used to sell? The original install was in 2012.

Thanks for the advice!

 

Low-impedance injectors are relatively uncommon, and neither the MS nor the Hydra requires them.

Why was the MS replaced? Did it fail, or did you or your tuner simply decide to go with the Hydra instead?

Aside from the destruction of the ECU, how was the engine running before that? Were all injectors firing reliably?


You're not giving us a lot to go on here. "My ECU died. Why?" isn't a question that has one simple answer.

 

The megasquirt was replaced because the car quit running at all due to burnt circuit in the computer. I replaced it with Hydra because BEGI refused to replace the megasquirt. . The Hydra has been installed since 2015 and has been running fine but I have not put many miles on it. With the current problem with the HYDRA, it was running fine and then started missing badly. My mechanic discovered that one injector wasn't firing at all and traced it back to the circuit board on the HYDRA. I'm assuming that since I've had two computers fail that there is an underlying cause inherent to the car.

 

That's the worst kind of problem...

At the car-side of the ECU connector, putting a meter between ground and each of the four injector drive lines, noting the resistance, would be a start.