curly

iTrader: (25)

With the setup listed below, my car won't start all of the sudden, just cranks and cranks. I started it for just a minute to move it yesterday, then came back an hour or two later and tried to start it. It started right up to a fast idle and in the course of 4-5 seconds died down and stalled out. It hasn't started since. I can plainly hear the fuel pump going, although I've tried jumping F/P and GND which doesn't help. There's a strong smell of gas coming out the tail pipe, so I guessed that I had no spark. I replaced the coils with another known good set, no change. I've taken all the spark plugs out (which look very wet btw) and cleaned them up, as well as jumped them to a ground to see if I had spark, which I seem to (my choice of ground was a little iffy, but I got shocked once and saw spark another time, so I'm assuming they're working). After I cleaned them, the only change is that every couple dozen revolutions, it catches once. As in only one or two cylinders firing for one revolution. I've also checked the fuses by the washer bottle, none were blown. Any ideas as to what I should check next? I was thinking about replacing the spark plugs since when I cleaned them up I did manage to get a combustion cycle or two, but I can't imagine that a 1 minute drive managed to foul them all to the point that it won't start at all.

Braineack

iTrader: (62)

try a new ignitor, possibly CAS. it's getting too much fuel, most likely from not sparking.

curly

iTrader: (25)

Thats what I'm guessing, no spark. Whats the method for checking the CAS to make sure its good? If there's a procedure in the Haynes manual just tell me that, I'll dig mine out and follow those directions. And is there a way to check the ignitor? I have a nice Fluke meter if that helps. Doesn't it seem weird that either of these would just crap out without warning over a matter of hours? It was literally perfect, than nothing an hour later. Oh excuse me I bolted on my front tow hook before I tried to moved it again.

curly

iTrader: (25)

oh and COPS don't get rid of the ignitor, do they?

patsmx5

iTrader: (16)

Verify spark agian and be sure. Also could try pulling the plugs, pull the CAS, and spin it. See if you get spark. Maybe pull the F/P fuse so you don't inject a ton of fuel in the motor and for safely. Sounds like an ignitor to me. what year is your car? 89-93 have external ignitors so it could be a bad ignitor. Sounds like that to me.

Braineack

iTrader: (62)

they do and replace it with 4 of their own.

curly

iTrader: (25)

Damn I almost want it to be the ignitor now...

I priced them out online, found a few for about $120-150, whats the going rate of a DIY or PNP set of COPs these days?

I will verify spark of all four cylinders tomorrow, my tests were with crappy grounding positions (is the valve cover a good place to ground a spark plug? there no paint...) and literally 30 seconds of my dad's time when he could press the starter button for me.

Its a '93 pat, with the external ignitor. And you're saying that by removing the CAS from the back of the engine and spinning it by hand with the ignition circuit on it should spark?

patsmx5

iTrader: (16)

Yeah, the MS looks at the CAS to determine RPM. Spin it and you'll get a reading in MT and sparks. I think braineack knows more about COPs and 1.6's than I do, so I'll let him school you there.

curly

iTrader: (25)

Uh, no Megasquirt unfortunitely. Is there still a way to test my CAS or ignitor?

patsmx5

iTrader: (16)

Ah, well their's your problem! J/K. You can still spin the CAS and should get spark. As for testing the components, I cunno. I have a 99'.

curly

iTrader: (25)

No joke about it pat, I'd take a megasquirt If I had the money. Man I wish the CAS wasn't such a pain to remove. But I'll do it tomorrow. Anyone else care to chime in on this plan before threeish tomorrow? That's when I'm starting

cueball1

iTrader: (13)

Hit up all the Miata used part shops for the ignitor. They should have plenty around. Partsgroup and the like. FM salvage has them for $50. Partsgroup seems to be a little less on parts I've priced.

Pisser.

curly

iTrader: (25)

Ha! cost me a grand total of $8.36 to fix. Ended up just needing some new plugs, which I have a talent of plugging, no matter what vehicle. Gapped the new ones at .030", it didn't seem to want to start at first but it caught a few more times then sprang to life, thank god.

I'm buying a set of COPs from mike rivelli, so I'll have no worries about coils, ignitor or plug wires soon, only my wiring job

Thanks everyone so much for your help, thankfully it didn't end up being anything too expensive.

Victory picture after I got it running:

patsmx5

iTrader: (16)

Car looks better when it runs, don't it? Stupid **** breaking is the worst. I should have said put new plugs at .020", as I normally say that to anyone with sparky problems. But you said you cleaned them.

FWIW- cleaning plugs is a black art. What I do is use a light wire brush and brake parts cleaner. Get the cleaned, spray 'em with brake parts cleaner, then let that crap evaporate. Check the gap and then reinstall.

curly

iTrader: (25)

Well they're now new plugs. I used a wire wheel on a bench grinder to try and clean them. Might of been too aggressive. I'll see how .030" holds up, but I have a set of COPs coming

patsmx5

iTrader: (16)

Yeah. FWIW-same technique works to clean O2 sensors.

curly

iTrader: (25)

I'll keep that in mind, if the plugs ate fouled I wouldn't be surprised if the O2 sensors weren't far behind.