2005 Mazda 3 Sometimes will not Start

Hello, I have a 2005 Mazda3 with a 2.0 engine & a five speed transmission and 94,000 miles. Since June the car has twice not started, and so far three trips to two different Mazda dealers have not resolved the problem. The car had sat overnight, when I tried to start it the engine it turned over normally, and sounded normal, for just a second. Then it sounded like it started turning over much much faster than normal and the turning over sound changed to the sound of a high speed “whirl” (I don’t know any other way to describe it). In both cases the car just turned over and over and never sounded like it was going to start, resulting in a tow being needed. I’ve now found out that the dealer started the car by pushing the gas pedal to the floor, then cranking over the engine and then very slowly releasing the gas pedal until the engine started to fire. In the three months in between the non start days the car has started fine and it drives fine, lots of power, constant power with no surges or bogging down. The dealers have checked the compression, fuel PSI, and run computer diagnostics and everything appears to be normal. They also removed the value cover and say that as far as they can tell the fuel injectors seem to be functioning normally.

Has anyone else run into this problem and if so how was it resolved?

Thanks for any help you can provide.

That ‘whirl’ sounds like the starter solenoid doesn’t cause the starter gear to engage your flywheel’s gear.

I’m assuming the check engine codes – current and pending – show nothing. And all engine fluid levels are at spec and routine manufacturer’s scheduled maintenance is up to date.

It sounds like either what @RemcoW said – the starter isn’t engaging the flywheel correctly – or there’s a compression or valve timing problem.

It’s relatively easy for a mechanic to verify or eliminate the starter as the cause, by removing it and doing a bench test and visually inspecting the flywheel teeth. That’s a good place to start.

If that’s not it, and since the compression checks out ok, it possibly may be the valve timing is out of whack somehow or another. A visual check of the timing belt or chain might be in order.

Remco & George, Thanks for the idea on the starter/flywheel, I’m going to have them checked out. Engine codes all check out OK, 5-20 syn oil chg’s have all been done by me. Car does not use any oil. Timing has been checked twice and is OK as has the compression & it is OK too. The timing chain & tensioner are OK. Thanks Again.

I’m inclined to agree with Remco & George. Know also that this condition will not cause fault codes. The OBDII system monitors only those things that might affect emissions outputs. Starter related issues are not amoung those things.

I find it distressing today that so many young techs cannot disgnose a problem if it doesn;t store fault codes or fall into their diagnostic instructions from the manufacturer.

I’ll vote for a bad starter also. I went through this on another car. The problem was the overrunning clutch on the drive gear. It prevents the (running) engine from spinning the starter before the gear retracts. The clutch was weak, and sometimes it slipped when it was supposed to engage. I mention this because there is no external evidence when it is bad.