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Hi everyone, I have a problem with my 1998 nb, cranking and no start or running rough for a short time then stalling.
swapped the coil pack with a good one. ran like a dream for a short time. then when attempting to start an hour or so later, cranking fine but no go. My car only has the underbonnet mazda diagnostic box. Is it possible to check the cam and crank angle sensors with a multi-meter and if so what figures should i see, ohms, volts etc.
earth strap looks ok, but i am about to give connections a clean as advised on another post.
Any other advice most welcome.
Thanks.

Given the reaction you got following swapping coilpacks, if you haven't already it's also worth checking the wiring to the coilpack as it deteriorates where it deflects just prior to plugging into the coilpack. Apparently the combination of deflecting & not being well supported in this particular spot, probably compounded by alternating high & low temperatures, weakens the wires. It's not immediately apparent to the eye, but if you move this part of the wiring loom around while the motor is running you'll get a response in terms of idle if there's a problem. Good luck!

See http://www.boostedmiata.com/pdfs/1999-2001%20Service%20Manual.pdf and http://www.mellens.net/mazda/index.html

Thanks for your help. will try all those things. hope to get some time to do some more work this week.

Found a dodgy wire to the coil pack, replaced that but would start and run for a few seconds only. Worked my way through all the checks I could. No faults using a led at diagnostic box. and i had spark to all plugs. Changed the fuel filter, same, checked the fuel pump, no noise, but had power at the connector. Fitted a new fuel pump and hey presto its all good.
The front crank seal had a small leak, so changed that. Putting it all back together one of the crank pulley bolts snapped. After some choice words and a lot of effort, managed to remove the broken bolt, replaced all the pulley bolts. Did a test drive on my nearby test road. came home grinning. Thanks for the post replies, They helped out big time

Great to hear that you pinpointed particular issues - hopefully that sorts it. Interestingly there seems to have been a spate of NB8A fuel pump issues this year.