Blown Fuse, Won't Catch

[gabkwong]

My 99 NB was driving fine on my home today. All a sudden the engine died when I cursing at 65MPH. The tach needle went all the way 0 even it was still in 5th gear! After I parked it, it would crank but no catch. I checked the fuses. The 15amp labeled 'engine' by the kick panel was blown. When I cranked it again, it blew again. I than check the big fuses under the hood. The 40amp was blown too. I replaced both, it would crank and not catch. Again the 15amp fuse blown with each time I crank it. The new 40amp fuse stay good.

What do you think I should do next to fix it?

Thanks!

[sammm]

Bad main ground or a shorted wire somewhere would be my guess.

[SirHustlerEsq]

Get your multi-meter and start testing resistance from the fuse block to the sensor.

[POS Racing]

Bad main ground or a shorted wire somewhere would be my guess.

I was thinking the same thing.

Have you posted this problem on Miata.net? It may not hurt to ask this question to a larger audience.

[SixAce]

I was thinking the same thing.

Have you posted this problem on Miata.net? It may not hurt to ask this question to a larger audience.

+1, also, have you checked the battery, terminals, main cable routes, etc. Seems like it would take a lot of juice to blow the big fuse..

[motorollow]

Did you tow it home last night?

[cam76034]

I'd start at the battery. Any way it could be shorting out there, battery slid over, something metal grounding out the positive cable? Maybe you should curse more slowly?

[trickyrix]

Is the fuse supposed to be a 15A? I know it's marked "engine" but what does it actually run? Fuel pump? ECU?

[motorollow]

I believe he may have a short in the fuse box under the hood. He recently replaced a relay in the fuse box and we found that problem by accidently wiggling the box and hearing it arc.

[trickyrix]

Could be Gremlins...

1. Avoid bright light.
2. Don't feed after midnight.
3. Don't get it wet.

Or else...

[POS Racing]

Could be Gremlins...

1. Avoid bright light.
2. Don't feed after midnight.
3. Don't get it wet.

Or else...

Well Played Mr. trickyrix!

[jeff_man]

Make sure your o2 sensor isn't melted to your mid pipe. Happened to me and Gary once before on our NBs with the same description.

[motorollow]

Make sure your o2 sensor isn't melted to your mid pipe. Happened to me and Gary once before on our NBs with the same description.

That's a good suggestion since he has had issues with the O2 sensors before.

[jeff_man]

That's a good suggestion since he has had issues with the O2 sensors before.

in both cases the wire was rapped around the o2 and melted the wire covers and grounded the system.

[gabkwong]

Some thing definitely shorted out! Battery..checked, O2 sensor wiring harness.. checked. Relay under hood .. checked. I am thinking it may be the fuse box under hood itself is the cult pit. Something on the underside of the fuse box is corroded!? Anyway, I am clueless when it comes to electrical stuff, besides many other things. Under the advice from Gary S. and others, it is towed to Town North. I am requesting Jim Qutterbin to work on it. Definitely, it will be wallet biopsy. I just hope that it does not turn into a wallet-ectomy, separating me from my credit card!

[black roadster]

Jim Otterbine and he should be able to help you. Tell him we referred you. Did you check both O2 wiring harnesses?

[SixAce]

Update?

[motorollow]

I believe the dealer is just getting to it today.

[POS Racing]

Update?

+1

[motorollow]

Jeffman wins the prize. It was melted O2 sensor wiring.