UrS695

I blew the ECU fuse this morning - the 15amp that sits above the ECU and car died. It came on as a sudden failure while driving down highway at 70mph.

After replacing the ECU fuse the car started right up but runs very rough like it is running on 4 cylinders. Any ideas???

Could I have blown a coil that caused the ECU fuse to blow and now the coil is shot???

TIA

- GT Style -

Try detaching battery for awhile to reset ECU.

4Driver4

Either a coil meltdown or one of the coil wires chafed and broke. Most likely a coil meltdown.

SilberUrS6

Or is there a condition under which it shorts, and then becomes open again?

4Driver4

But since it hasn't blown again I'm guessing it's a coil that blew and took the fuse with it. It happened to come rest open rather than shorted.

cpayne

Hijack: Ahhhh..dont put that "trumpet" BOV on the car!!! Yuck! You want sound go CAI.

4Driver4

...have a CAI on the Miata. <hangs head in shame>

SilberUrS6

That makes sense. Thanks for the explanation.

cpayne

CAI properly done<> shame...BOV...hmmm

UrS695

Took the coil cover off last night and the #2 coil had some goo leaking out of it tnd ther was a smell of burnt plastic. Did the POS switch and dead cylinder stayed on #2 so looks like #2 coil shorted then went open circuit therefore ECU fuse stayed intact and car could run on 4 cylinders.

Now I need to find source for coil or look into the 1.8T conversion - any suggections?