Help! Miata won't start

Hi,



I have a 1999 Miata with 20k miles on it that won’t start. It cranks and occasionally sounds like it’s about to start (a rough start of idle) but always fails. I just checked the battery and it reads 12.3 Volts. I tried a jump start with another battery that had 13 Volts but it didn’t help. I checked the fuel pump fuse under the hood and it was intact. I have a full tank of gas

and full oil. New plugs and wires were installed (by me) about 1000 miles ago.



I don’t have the knowledge to do any type of major repair, but I’m hoping perhaps there’s still something simple to do that I haven’t tried. At a minimum I’d like to diagnose the issue further so I know what to expect. Any advice would be greatly appreciated!



Thanks!

Also, both the check engine and battery light remain on with the keys in the ignition.

You need to relax. Check if the spark plugs get spark. Remove a spark plug wire one at a time from the spark plug end of the wire and have an assistant crank the enginge while you hold the wire end 1/4 to 1/8 inch from a clean metal area you can reach. This will show if you have spark at all your wires. You only need to see a good two or three sparks to know the wire is good. stop the engine and move to the next wire. Have you checked the plugs for fuel on them? Problem is you may not get a code until the engine runs. Can you borrow a code reader from a parts store? That might be a big help. They usually want a deposit but you get that back. Post your code here if you get one.

Every engine needs spark and fuel, and a whole timing belt. At 11 years old, your car should have had its original timing belt changed years ago. Even if it’s not original, the timing belt could be bad. The REPAIR MANUAL should show you how to check for spark and fuel, and timing belt integrity. Got one?

You can get one of these for about $5 or so to check spark.

http://search.harborfreight.com/cpisearch/web/search.do?keyword=spark+checker&Submit=Go
Get a name brand can of starting fluid with straw, spray into throttle body, remove round tube from air cleaner at the motor.
If you have spark and it starts you know it is fuel trouble.
If it does not start I would think it may be timing belt.
Spark checker and starting fluid will work on any motor and are good to have around.

When was the last time you replaced the spark plugs and wires? On this car it sparks each plug twice as often as most engines. That is hard on plugs and wires. My personal experience is that the fancy expensive plugs and wires perform less well than the OEM brands. The OEM plugs also seem to fit better.

Well, after a couple days of the same no-start condition I tried again tonight and after a couple cranks it fired up and was running smooth within a few seconds. I then proceeded to let it idle for awhile and then took it on a 20 minute drive. Everything seemed fine during the drive, and when I got back home I tried starting it up again and it fired up immediately.

Does this offer any clues?

The spark plugs and wires were replaced about 6 months ago.

The day is won’t start, was it a rainy, wet, and humid day or evening? I suspect your replacement wires could be “cheapies” and are affected by moisture in the air. If you live in AZ disregard.

My 2001SE with just under 40,000 miles started stalling and hard to re-start.Spark plug replacement did not cure it. The fix for my Miata was new coils. It has run without stalling since.

NOTE: Miatas have a system that fires each plug twice as often as most other cars. That means plugs don’t last as long, but more important it also means wires only last half as long. It sounds like a problem that replacing plugs and wires will fix it up. I also would consider replacing the coils as zoomboy suggested.

I think the car just got flooded for some reason. It’s interesting that an EFI system shouldn’t flood, but I’ve noticed this happen at least on three different occasions with three different cars and makes in the last 6 months. Next time this happens, press the throttle wide open and try to start again. If it is flooded, this will help clear it out.

And, sorry Joseph, I disagree with the notion that a wasted spark system makes plugs and wires last half as long. I’ve dealt with wasted spark ignition systems since the mid '80s, and have not witnessed any shortened plug or wire life.

The engine might be flooded, when cold. To un-flood, hold the gas pedal to the floor while cranking the engine.
Contrary-wise, the engine might be too lean to start. Then, use the starting spray in the large intake tube, and crank. You might play the gas pedal a little during start.