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Car Starts Every Time -- Except When It (Rarely) Doesn't

This winter, my always reliable 2002 Subaru Outback has refused to start twice – once on a Sunday morning after church and once after an evening meeting – in other words, both times when my mechanic was unavailable.

In both circumstances, it was very cold. However, the car had already started fine earlier in order to get me to church and to my meeting. Afterwards, however, when I turned the key, I had plenty of “turnover” (in other words, the battery was fine), but absolutely NO “catch.” Nothing happened. I tried mutliple times – with no gas, with pedal halfway to the floor, with pedal all the way to the floor – and the result was always the same. No catch at all.

In one case, the car had sat about 1-1/2 hours after I arrived and, in the other, about 2-1/2 hours. Both times, the car had started earlier, after having sat for many hours (overnight and longer). I’ve also had no problem starting it other times, after short, medium, and long times sitting.

No check engine light has come on; nothing shows up on the diagnostic computer. And, oh, of course, both times, when the mechanic got to the car many, many hours later, it started right up.

My mechanic just can’t figure it out. Can someone help? I love this car, but now I no longer trust it, even though it starts every time – except on those two rare occasions when it didn’t.

Thank you!

Subaru crank sensors can be infuriatingly intermittent when the weather gets colder. They’ll work and then they won’t, causing you to not have spark and not start.

You could get a spark tester at a car parts store. It looks like a spark plug but it clips onto the engine. When hooked up like a spark plug, it will arc so it will be be an indicator whether you have spark.
Next time it doesn’t start, pull a spark plug out and put it on this tester. It will show you whether you have spark or not. If you do not, I’d start by replacing the crank sensor. They aren’t expensive and relatively easy to replace.

That^ is where I’d start. If you do indeed have spark but no start, I’d then check the fuel delivery.