99 NB won't start using ignition switch.

[Keifersmith]

Friday at work my key got stuck in the ignition switch on my 99. It would turn from ACC to START but wouldn’t turn back to lock so I could remove the key. I stopped by a local locksmith who managed to remove the key, cleanup the switch cylinder and cut a couple of new keys per the vin number. When I went to pick it up the car wouldn’t start. Everything seems to be normal except when the switch is turned to START… nothing. I do hear the fuel pump when I hit the ON position. It basically acts just like I was trying to start the car without pushing the clutch pedal to the floor first. Tonight I went back and pushed started the car and drove it home so it will start/run fine, just not using the ignition switch.

Oh yeah, if I turn the switch to START and hold it there for a few seconds a little wisp of smoke starts coming from the back side of the switch, so I’m guessing it’s getting power but maybe shorting out or something? I haven’t had a chance to look at the interior fuse box to see if I see any fuses there that might be a problem but I’m guessing that’s not it as it does seem to be getting power.

Before I go buy another ignition switch, is there anything obvious I should check?

TIA,
Keith

[black roadster]

Tou can service and rebuild the ignition switch. Look it up on m.net. I cleaned and regreased mine with di-electric grease.

[motorollow]

This happened to me in the 1990 I had. My recommendation is buy a new ignition like I did. My ignition was never the same even after getting the key out and lubing it. It just got stuck a 2nd and 3rd time. And it will get stuck at the most inconvenient time possible.

[Keifersmith]

Got the car back up and running today. After checking fuses I pulled the ignition switch out and tested continuity on the various switch positions. It tested fine so I plugged it into the harness and used a screwdriver to turn the switch. Car started right up with no problem. I put the switch back in the ignition assembly and tried using the key again, car wouldn’t start. I’m not exactly sure what happened but it looks like using the key doesn’t quite turn the switch assembly far enough to engage the start position, even though it is turning through the entire range of motion. Guessing maybe shaft that runs through the assembly might be a little twisted or more likely the key cylinder where it mates up to the shaft might have gotten damaged.

Anyway, I visited Mario at Mazda Heaven and picked up a used ignition assembly, took it back by the locksmith and had them re-key it to match my original key. Problem solved.

[Keifersmith]

When the key was acting a little flaky I used some dry graphite on the lock to help lubricate it. Per the locksmith, They said never to use graphite on locks, that it will actually jam up/damage the inner workings over time. That was news to me as I always had heard to use the graphite instead of WD-40, etc. Don't think this was the cause of the failure but it probably didn't help. Needless to say they do sell "lock lubricant" specifically for this purpose.

[sammm]

I usually squirt some silicone spray in a lock if it starts getting sticky.

[ptech]

The tall thin Miata keys can get twisted easily if you get a little too aggressive with it trying to unlock the console or trunk. It then can get stuck in the tight clearances of the ignition cylinder. This happened to me once. After I finally freed the key I tapped it flat with a hammer.