Car question.... why the dead battery?

**smmokan** · 03-10-2008, 09:24 AM

The last two times I've washed our cars, one of them hasn't started the next morning. First it was my '06 Mazda 3, then this morning it was our '07 Suby Impreza. From washing the cars, is there some water or soap getting into the alternator or starter or something? I've never had it happen before, but now it's happened twice in the last month- both times after I washed the cars on a nice day. Anyone know what's going on, why isn't the car starting?

**hutash** · 03-10-2008, 09:40 AM

Some how I doubt an '06 or '07 has a distributor cap.

Most likely just coincidence, but to be safe, leave the engine running when you are spraying under the hood, and stop if the engine sputters or runs rough. I wash my engine compartment all the time without ever having a problem. Most new cars have their electronics pretty well protected from water. The only other thing I could think of is a loose battery terminal that got wet and had decreased contact.

**smmokan** · 03-10-2008, 09:47 AM

I think its too much of a coincidence not to have something to do with the water or soap used when washing the car. Combined, both cars have had dead batteries twice, and both of those times were in the last month the morning after I washed the cars.

**iceman** · 03-10-2008, 09:57 AM

Probably some number of millions of cars get washed in this country every day and start fine the next day. Are you doing something funky like using a pressure washer on the engine compartment or something?

**hawkgt** · 03-10-2008, 09:59 AM

tough call without more info....

Do they turn over at all? if so, and no start then I would guess water in gas. This can happen due to condensation in the tank from washing... get some HEAT or something like that and put in the tank and keep the tank topped off. When driving around with less than 1/2 tank of fuel increases the chance of condensation in the tank.

If they do not turn over at all, dead battery. You may have a short or light on somewhere. I know I turned on my back light in my subi and killed the battery after washing last fall.....

**smmokan** · 03-10-2008, 10:44 AM

Yeah, sorry for the confusion.... each car once. Mazda first, Subie second. I wasn't spraying water under the hood either.

**timvwcom** · 03-10-2008, 11:06 AM

I'll ask this question even though it makes it sound like I don't trust the description above... Sorry. Two typical incidences of car not starting;

1. Dead (uncharged) battery - barely turns over to start or just clicks or nothing happens when you turn key.
2. Gas/Spark issues - turns over OK... but just never "fires" or sputters then dies. If trying to start long enough, this can also eventually drain the battery.

Also, the method you use to get them running again may tell us something. Do you jump start using other cars battery, use plug-in battery charger, wait a day then it starts fine...

I have several ideas, but won't waste time to chase up all those different trees until you give me/us some more specifics...

**Rontele** · 03-10-2008, 11:25 AM

To get the suburu running again, I'd suggest a healthy dose of K.D. Lang music followed by some Indigo Girls

BLOOD SWEAT STEEL · 03-10-2008, 11:27 AM

Originally Posted by Rontele

To get the suburu running again, I'd suggest a healthy dose of K.D. Lang music followed by some Indigo Girls

...after donning your pantsuit, of course.

**smmokan** · 03-10-2008, 11:39 AM

Tim- dead battery and it was jumped using another car's battery.

**TeleHoar** · 03-10-2008, 11:40 AM

Simple
Car washes are AC,
Cars are DC.

I have the same problem after I bring the toddlers into the car wash for a quick hose-down.

**Beaver** · 03-10-2008, 11:42 AM

Were you listening to the stereo as you vacuumed it out? Didja leave the interior light on all night?

**72Twenty** · 03-10-2008, 11:42 AM

Don't leave the dope light on.

**Tye 1on** · 03-10-2008, 11:46 AM

This would play well on Car Talk.

**smmokan** · 03-10-2008, 12:14 PM

Battery wasn't in use while washing the car. I'm smart enough to close the doors and windows while I'm spraying water all over the car.

**timvwcom** · 03-10-2008, 12:38 PM

Originally Posted by smmokan

Tim- dead battery and it was jumped using another car's battery.

Well... the obvious next step is to ask what color the car is and how you spell your first name?

In all seriousness, short of just a random occurrence, I'd say there are really only two categories of likely possibilities;

A) User action; forgetting a dome light on, leaving a door ajar, leaving radio on.

B) Electrical drain caused by short circuit (which as mentioned earlier, would likely happen in heavy rain/driving conditions); water shorting contacts that remain "hot" while car ignition is turned off.

I'd say just refrain from heavy spray at grill(e), power antenna, door jambs??? Not much else I can think of right now...

**Chainsaw_Willie** · 03-10-2008, 08:13 PM

Originally Posted by TeleHoar

Simple
Car washes are AC,
Cars are DC.

I have the same problem after I bring the toddlers into the car wash for a quick hose-down.

The alternator is AC, that's why it's called an alternator, not a generator.

**gorms** · 03-10-2008, 08:26 PM

Originally Posted by Chainsaw_Willie

The alternator is AC, that's why it's called an alternator, not a generator.

I think by your logic it would be a director....no?

**hutash** · 03-12-2008, 12:46 PM

Originally Posted by smmokan

Battery wasn't in use while washing the car. I'm smart enough to close the doors and windows while I'm spraying water all over the car.

There's your problem, you are spending way too much time washing the cars. Just leave the doors and windows open, and hose out the interior

**Danno** · 03-12-2008, 01:02 PM

because of stuff like this, I just prefer to never wash my truck.

**Crass3000** · 03-12-2008, 01:41 PM

Iv'e noticed that when you leave your headlights on sometimes the car won't start. Since you don't really need your headlights on when washing the car or in general if not driving at night simply turn them off. Problem solved. You owe me one

**bio-smear** · 03-12-2008, 02:01 PM

Do the leads and terminals on the battery look clean and corrosion-free? Growing up in the NW I saw many times rapid electrolysis that would overwhelm the positive lead coming off the battery with corrosion/oxidation, enough to impede current. It was always during rain or super humid weather. Usually the action of pulling it off and brushing it would restore it.

I had a weird thing happen a while back. My bitchy neighbor bitch and I were in a war over a parking spot, and one night I came out to see she had NYC-style parked her battle-worn minivan bumper up against the front bumper on my Tundra, just mashed into it. I went to start it and the bettery was dead as fuck. After I verbally bitchslapped her and made her move her van, I pulled the Matrix over to jump the Tundra. 10 minutes worth of charging off the Matrix alternator and still not enough charge to start the Tundra. I ended up putting it on the battery charger overnight. In the morning it was fine. Never had a problme with discharge before, never since.

Something about mashing into my bumper caused my battery to discharge.

**P_McPoser** · 03-12-2008, 03:57 PM

Originally Posted by bio-smear

Something about mashing into my bumper caused my battery to discharge.

Weird, same thing happened last time I saw your mom.

**Chainsaw_Willie** · 03-12-2008, 07:45 PM

Originally Posted by gorms

I think by your logic it would be a director....no?

Hmm, good point.

Well, it may not be perfectly logical but a device that generates AC voltage is called an alternator and a device that generates DC voltage is called a generator, at least as far as cars are concerned.

I dunno why, but that's the way it is.