Ok I'm not a car whiz and my friend who works on my car with me is at work right now. My car won't start, I THINK it might be spark plug but not sure.

Lights turn on.
Tried to jump it, no go.

So I think battery is fine.

When I turn the key I get really rapid click click click sound. When I turn the key back the gauges vibrate for a few seconds.

01 Civic EX. Temperature dropped last night but not to freezing or anything, so don't think anything froze (if something can freeze).

Thoughts?

 

Sounds like the starter is not engaging...

 

Thanks. I also checked with my multimeter. It reads ~12v idle and when someone cranks it it drops to ~3v. On another forum I was told it's more likely to be battery (not starter). So which is it? Or will I just have to find out through trial and error?

 

Your subject line suggested that there was no problem with the battery, but given your readings it sounds like the battery or a connection to the battery. You should have about 14 V at idle, a 9 V drop when starting is excessive.

I would first check the connections at the battery.

A charger with a quick start should allow you to start the car.

 

I don't have a quickstart charger, but I can get someone to try and jump it again (maybe wait longer this time). The terminals looks fairly clean and it's clamped on well, but I can take the leads off and replace them. Maybe brush off the terminals too. Touching a single lead at a time with a wrench won't do anything bad, right? (as in won't shock me). Do I need to connect/disconnect them in any particular order?

 

If they look clean (not green, or flaking) then you don't need to remove them.

Touching a single lead will not shock you, I generally start with the positive side first and the reverse when installing

 

With engine off. battery should read no less than 12.6 VDC. If less, battery is suspect.
The cold snap killed it.

 

They look pretty clean. A little flakiness around the edges but minor. I've seen a lot worse still work.

Ideally I'd be able to jump start it tomorrow morning and drive it to the parts store and have them figure out what's wrong, but if that doesn't happen what I'd like to avoid (if possible) is taking out the battery, getting a new one, and then finding out it wasn't the battery all along.

 

It appears from all that you said that it is the battery. The voltage drop should not be that much when starting.

The other thing you can check if it is not a sealed battery is the battery fluid. There is a cheap battery tester (aka hydrometer) that cheks the specific gravity of the fluid. I can't remember the difference between the cells but a minor difference will mean that you can recharge the battery (I believe it is 30 points).

If there is a dead cell then you must replace. The original battery might have a built in hydrometer which should be green, otherwise it is time to replace