Car randomly won't start

I have a 2007 Mazda5 that randomly wouldn’t start one day, it would just click once and that’s it. Everything is getting power and we recently replaced the alternator, battery, timing belt, and ac belt. We were thinking it might be the starter but a week and a half later when we went to fix it I tried starting it up and it didn’t work the first time, just clicked again, but the second try it started right up. Can a starter slowly go out or would it most likely be something else?

Battery connections are the first place to begin when you have a “No Crank” situation. Even
if you have a new battery, if the connections are loose, dirty or corroded, you will not be
allowing the full flow of current to pass thru the connections. The connection may be
enough to turn on the lights, but not enough for the huge flow that is needed to operate the
starter. This is where many people say that they know the battery is good….”because the
lights come on”. This is no more a battery test than licking a 9volt battery. It only tells you that there is electricity…not how many volts or the amperage that flows from the battery.
Jump starting may have wiggled the terminal just enough to allow the current to pass and start the engine, but tomorrow you have the same problem.

First remove the cables from the battery and use a wire brush to remove any corrosion and dirt from the battery posts and the cable terminals. There is a tool with a round wire brush for this purpose, found at any auto parts store for less than $10
Before connecting the cables, apply a coating of di-electric grease to the battery posts this will keep oxygen away from the connection so that it will not corrode as fast.

It is just as important that the other end of the cables also have a clean connection. Remove the negayive cable from the battery again so that you do not short anything out. Follow both cables to their far ends, remove this connection and wire brush the connection and the cable terminal clean and retighten these connections.

If there was work done recently, there may have been an “engine to body” ground that was not installed following the work. These grounds normally run from the rear of the engine to the firewall and are uninsulated and most are a braided wire. If any of these are found unattached…reattach them.
Remember….this is not a “Sherman Tank” don’t over tighten the connections.
Tight…tight………………too tight…broke!!!


It happened on my Corolla recently,the car would start randomly. I had to change the 2 copper contacts and plunger inside the starter solonoid to make it work again. You can buy a rebuil kit on ebay for $10 if its a Denso starter.They look like this:Capturestarterrepairkit

1 Like

What @COROLLAGUY1 said. Happened to my ES300 after about 10 years. The solenoid contacts wore out enough to cause an intermittent no start. So if you’re sure the battery cable connections are clean and tight, the starter could be the problem.

One other possibility - the switch in the transmission that only allows starting in Park and Neutral. Next time it happens, try jiggling the shift lever. If it doesn’t start, try shifting to Neutral.

1 Like

Most likely it’s the starter. The reason it acts that way is b/c the solenoid contacts don’t contact the same exact orientation with that piston looking thing (in the photo above) each time. That piston thing rotates a little w/each cranking. So it’s like a roulette wheel when it gets “iffy”, win sometimes, lose other times. A replacement starter motor will contain new solenoid contacts. That’s the way most folks address this problem, replace the starter.

Verifying the battery connections are solid as the poster above suggest is where to start though. If that’s ok, replacing the starter will likely fix this problem. To be sure you’d have to have the shop do some voltage measurements, but most people with this problem seem to just replace the battery and starter and that fixes it 95% of the time.