Battery or engine? and - tow or DIY?

I am going to preface my question by saying that my auto knowledge, though regularly augmented by Tom & Ray, is pretty minimal. So, this is a pretty basic question.

I spent 2.5 months this summer working and traveling abroad, and my car sat at home in my driveway. It was in need of a tune-up before I left the country, but I decided to wait until I was back since it didn’t make much sense to service the car only to let it sit for the whole summer. I asked my subletter to drive the car occasionally, and I’m not sure that she remembered to do this until a week or so before I was coming back. The week before I came back to the US, I got an email from her saying “your subaru is not starting.” She and a friend tried to jump the car to get it to start, thinking the battery was dead, but the jump didn’t work and the car would not start. She suggested that it was an engine problem, not a battery problem, because a jump should have done the trick.

So - I am now home, and sure enough cannot get the car to start. I was told last summer that I needed to replace the battery, but I never did it because it was a less urgent item in a long list of expensive repairs. So, my question is this - if the battery is completely dead and needs to be replaced, and sat un-driven for 2 months, would that prevent the car from being able to start with a jump? Or, is my subletter right - this is probably an engine issue, and a jump should have made the car start?

My other question is this - does it make sense for me to go out and buy a battery and try to replace it on my own, knowing that I will be taking it to a mechanic anyhow, or should I just have it towed directly to a mechanic? Will I save money replacing a battery on my own, or will it make no cost difference if I take it to the mechanic?

Thanks in advance for your suggestions!

What is in the “long list of expensive repairs”?

Your car no doubt needs a battery, but I would do the NECESSARY repairs as well first. Since you have neglected the car so far, it would be wise to have it towed by the AAA (if you can get it done or free)to a good mechanic who will diagnose what needs to be done to get it to start and run reliably. This is not the job for a tire shop, muffler shop or similar chain. They will just repalce everything they think needs doing without doing a PROPER DIAGNOSIS.

A battery sitting idle that long without use can dischrge to a point where it will no longer take a charge. This is especially true if the battery is three years old or older. The reason it wouldn’t start when a jump was applied is because the dead battery is drawing all the current that’s supposed to be applied to the starter. Try jump starting it again. Only this time allow the donor vehicle to idle at around 1200 RPM’s for 10-15 minutes. Then see if it starts. If it does start, then you’ll know it’s the battery that’s the problem and it should be replaced.


Since you are fairly confident that you are due for a battery, regardless of any other problems, yes, you should go get a battery and install it before you invest time and money diagnosing any other possible problems. If the battery is poor/failed, the mechanic will replace it before he tests anything else, and it will cost twice as much as if you had replaced it yourself.

Remember that a new battery will arrive only partially charged. If you determine that you have other problems as well, connecting the new battery to a battery charger will give you a better starting point for diagnosing other problems. In the absence of a battery charger, you can connect it to another car with jumpers, start the other car, and let the other car run at fast idle for 15-20 minutes to charge your new battery, but that is a very inefficient battery charger.

If the battery is more than 5 years old, then replacement is a good bet in the absence of diagnostic information. Cleaning the cable connections on the battery (I prefer steel wool for this task) will be a good plan whether you replace the battery or not.

If there is a Costco near you, I think that you will find that they offer the best price/quality on car batteries.

Yes, it’s possible for an engine to refuse to start with a bad battery in place, and especially if some lousy jumper cables are involved.

When you jump the car does it make a solid “thunk” type of sound when you turn the key? If so, this could point to a seized or blown-up engine.
Has your subletter provided any info about exactly what transpired that causes her to say it’s an engine problem? Lack of oil for whatever reason or a broken timing belt could cause a major problem.

The best way to verify if the engine is seized is to use a socket/ratchet on the crankshaft bolt and attempt to turn the engine by hand. If you cannot turn it the engine is locked up. Also check the oil level and try to figure out just how many miles were put on the car while you were gone…

Save some $s replacing the battery yourself and follow Manolito’s advise.

Thanks, all.

The “long list of expensive repairs” was from last summer, before I relocated from New England to the Southeast. It included everything from replacing a wheel bearing to replacing my wiper blades - I eliminated “new battery” and “wiper blades” from the list, and had all the other repairs done before I hit the road, expecting that I’d have to replace the battery at some point in the future. (I can’t recall now what they all were, but I’ve got the records somewhere.)

So - I think I’m going to take Manolito’s suggestion, and find a friend who can drive me to get a new battery, and maybe assist with the installation (though I have a handy DIY book that should help me with that, too). Then, I’ll take the car to the mechanic for the tune-up, provided that the car starts.

My subletter is out of town, so I haven’t been able to talk to her about it at length - but I doubt she let the other car idle for 15-20 minutes. Her pronunciation that it was an “engine problem” was based solely on the fact that she could not get the car to start with a jump, but my hunch is that the battery is problem #1.

Any advice on buying a new battery that I should keep in mind before I make my purchase? Should I take out the old one and bring it to the shop with me when I buy the new one? We have a Costco in the area, so I’ll either borrow a friend’s car or bring them along for the ride and try there first for a new battery.

Thanks again for the advice!

Agree that since you have already done the necessary repairs, it would likely be the battery. In that case You can with the help of a friend install a new battery. My wife did just that when I was overseas; she bought a new battery at Costco and our neighbor istalled it.

If your car sitter tried to jump-start the car perhaps she put the clamps on wrong and the inline fuse is blown…check this first.

Just where would this “inline” fuse be located.What’s it protecting? Subarus have a “inline” fuse on the cranking circuit? What’s it amp rating this would tell what it’s protecting.Ever put the cables on backwards? it blew the battery in half,sounded like a 30-30 going off

It is a fuse that is inline before the rest of the fuses on the power side of the battery…protects system from incorrect hook-up…should be on the positive side of the battery cable…happened to me when someone screwed up jumping my car.

Jump starting is highly over-rated. Can’t tell you how many times a jump with a poor quality cable didn’t do a thing. Maybe a professional car starting unit, but just jumping a dead battery won’t do it.

It requires a new battery, that still needs to be fully charged after buying it. Normally should not be a big thing to just put the battery in and start it up, but you sub letter could have fouled the plugs etc. trying to start it. So bottom line, might be best to just tow it in and let them deal with it all professionally. Would have been better to just leave it alone than having someone start it up.