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Car Batteries

About 4 weeks ago bought a new car battery for a 1994 Toyota Corolla. My car is now having problems starting. I was told by 2 different people that the new battery was too small for my car. Could that be the problem?

I can’t envision a battery too small for a '94 Corolla, except a motorcycle battery. But even if it was undersized, it would still work if the engine and starter were in good shape. It just wouldn’t last as long.

Exactly what is the car doing (or not doing) when you turn the key?

Even a “too small” battery will easily start your car if it is fully charged, especially in warm weather. For whatever problems you are having, look elsewhere.

Have you had your alternator checked? It is very possible that the new battery is not receiving an adequate charge from the alternator.

Group 35 is the correct size for that vehicle; we own one, so I know that for sure. If you buy an OEM spec battery, and I think the cheapest ones in this group are, then the battery should be OK from the cranking amp standpoint.

What about other maintenance: plugs, filters, etc? Look elsewhere for the problem, and pls beter describe the hard starting issue. Neither of our Corollas have had trouble starting in any weather.

Sounds like you have other electrical problems there…like possibly a alternator or starter problem.

Why are people telling you the battery is too small? Isn’t the replacement the same size and rating as the one you replaced? If not, it should be. I don’t think that is the source of your problem though. I agree with the others that it could easily be another component of your electrical system.

Thanks for all of the feedback I suspected that it had more to do w/my starter or alternator than the size of the battery itself. I should have mentioned that the car does not turn over whatsoever if it has sat more than one day w/out being driven. No clicking, no lights, no nothing…completely dead. Thanks again.

OK, so have you ever had either starter tested or a charging system test on the car done? Was the battery just a “best guess” and no testing of the alternator done?

Back to some basics, like making sure all the electrical contacts are clean and good; that the grounding is OK. Does the car start when you jump start it? If so, do that, and get some voltge readings from the alternator by using a volt meter and tell us what they are. That should verify alternator is OK or not, for a start. When you do drive the car before it sits, how long do you drive and under what conditions?

Your problem isn’t the battery. Any 12VDC car battery will start that engine fine. It’s a small 4-cylinder, modest compression (meaning it doesn’t have to have a big electrical motor drawing lots of current to turn it over or require an especially high voltage spark like a high compression V8 supercar engine would). It doesn’t need a big power battery.

What is it doing when you try to start it?
Is it just clicking? Is it doing nothing at all? Is it turning over but not firing?

Why did you get a new battery, were you having trouble with starting the car? I think you may have a bad battery, new, but bad.

I think I had the same problem with my '96 ES. It is not the battery or alternator. Toyota starters have two copper contacts within the solenoid that wear over time as they contact a copper disc on the end of the rod that pushes the gear to mesh with the ring gear. The contacts are about $15, and you should replace the disc/rod also. If you don’t want to take the starter apart (it’s not difficult) replace the starter. Worked for me.

If the battery starts the car fine but goes utterly dead overnight, it seems likely that something is draining the battery. Like a light remaining on or an electrical system problem, like a bad alternator. A test (which you can do or a mechanic can do) is to take a DC ammeter and put it in series with one of the battery cables. See what the current drain is at rest (don’t try to turn on the ignition or start the car) If the drain is more than a few hundred milliamps, I’d guess you have a problem. Start pulling fuses until the problem goes away. If you have no experience working on cars or electricity, I wouldn’t expect you to try this test. But a car battery that is starting the car just fine in the day should not go totally dead overnight. Have it checked. Many places will test the alternator for free—for the rest of the electrical system you may have to bite the bullet and pay a diagnostic fee.