About two weeks ago our 1996 Miata 1.8L wouldn't start for my wife. A few hours later I went out and let it crank and crank for a while. Just before the battery was about to crap out it started and drove just fine, until Sunday night. My wife was driving when the car just died. So we had it towed home. I determined that the fuel pump was not working so its been replaced. At this point I'm pretty sure the pump wasn't working since I couldn't hear it humming before I replaced it and now I can hear it loud and clear. But the car won't start.

After messing with just about everything I could under the hood, I have found out the following.

1. I have spark. I also cleaned the spark plugs to be sure.
2. Fuel is getting to the fuel rail. I removed the fuel pressure regulator and fuel squirted out.
3. I think the camshaft position sensor is working. I unplugged it and I no longer had fuel or spark. Plugged it back in and I have fuel and spark again. But that is the extent of what I was able to test on it.

I've tried spraying carb cleaner into the intake, but still wouldn't start.

The only thing that produced any change was by cranking the car over for a bit. Then I unplugged the fuel pump and it tried to start and stumbled at a very low idle for about 5 seconds and died.

Normally this would make me think it was the fuel pressure regulator, but even with the fuel pump disconnected, I would think that with spraying carb cleaner into the intake would get it to start for a bit, but no such luck. Also I am smelling fuel which is what made me think it was flooded and unplugged the fuel pump


The fuel pressure regulator is $130+ !!! Not something I want to just replace if its not the problem. The Camshaft position sensor is almost $350!

So I would like to narrow this down a bit more so I don't go for broke replacing everything under the hood.

I can't seem to find the timing marks to verify proper ignition timing. That is the only other think I can think of.

Thanks for any and all suggestions.

 

DO a compression check and if you have compression if so i would think it is flooding which would be to much fuel .

my car has 2 leaking injectors and is hard to start in the summer time the presser build up in the tank make it leak if i unscrew the gas cap it will not do it

 

It was a timing issue. Got down into it and double that the woodruff that goes in the key way that the crank timing belt sprocket was gone. So I have no idea how this happened but who ever worked on it last messed something up. But lucky since this is a non interference motor nothing in the engine was hurt. New timing belt and tensioner, water pump since I was there and of course a new woodruff key and it was all good.

 

That would do it every time.

Was the crank keyway damaged?