Last thing I need is more car trouble...

October 13, 2009 7:21 PM

Why did my Subaru outback lose power steering on this rainy night?

My car is a Subaru Outback, 2000.

I drove to work in torrential rain on a flooded, hilly highway (Hwy 17 in N. California). The car handled perfectly fine both ways but something weird happened on the way home. Right after I came down the hill, both my brake system warning light and my charge warning light came on. It also became very difficult to steer. Luckily, I was close to a left lane exit and I pulled off safely and parked.

Turned off the engine, waited and turned it back on but both lights were still on and it was still impossible to steer. I had to wait 45 minutes for a ride and the situation did not improve over that time. The car starts just fine, and I am able to move forward and backward, just can't steer.


What happened? Two things to consider:

a) I had my car last checked by a Subaru specialist in June. I had my head gaskets replaced and had him look over everything. Nothing obvious was wrong at that time.

b) My car has been fine since then.

c) I also drove through several deep puddles today (much of the hwy was flooded).

My car is fine overnight but I will have to get it towed first thing tomorrow. Did I snap something simple like a belt, in which case I can just tow it somewhere local and get it replaced right away. OR Is this something more complicated that I should just get it towed to my Subaru guy (25 miles away, harder to retrieve car etc)?

I appreciate any advice to minimize the inconvenience.

posted by special-k to travel & transportation (15 comments total)

Let things dry out completely, and see if your situation improves.

Improperly-tightened (i.e. loose) belts will slip when they get wet, and with all the rain you drive through, that's very likely. Chances are very good that your alternator and a/c compressor were also out of commission while the belt slipped, but if the power steering pump bearing is a little tighter, it may take longer to grip again.

Even if you can't fix it yourself (let me know if you feel like trying, I can likely, uh... write you... through the process), it should be a very cheap repair.
posted by TheNewWazoo at 7:28 PM on October 13

Open your hood and check the accessory belts. Are they still there? As TheNewWazoo says, the belt will slip when it gets wet. It'll probably make a horrible shrieking noise while it does that. However, they don't tend to slip for very long. A few minutes of operation should clear it up. What is possible, however, is that the belt jumped off the pulleys when it encountered that much water. I've seen it happen on other makes and models. (Lots of flooding here in SC.)
You can ascertain this yourself, easily. Just pop the hood and look at the front of the engine. The alternator is at front and center, right on top of the engine on your Subie. Is the belt still on that pulley? If it's just the belt, you can take it anywhere or do it yourself. That's the most likely scenario, the telltale sign being that your power steering has also failed (the pump is belt driven).

PS: In the future, be REALLY CAREFUL about driving through deep puddles. This past rainy season, in South Carolina, I've replaced two engines in cars that were driven through deep puddles. If the engine sucks up water instead of air, big important parts will instantly bend or break inside the motor.
posted by Jon-o at 7:50 PM on October 13

Thanks guys. It was raining really hard and I had the music on so I heard nothing. After I parked, I quickly popped the hood to make sure my brake fluid wasn't empty. But I didn't notice the alternator (sorry, not good with engines). I am a fairly conservative driver but the flooding was pretty much impossible to avoid.

So on this page, someone else describes the exact symptoms I had:

today, while I was driving, the windshield wipers became very slow. Then I noticed that the brake light and the charging light were on on the dash. Then I lost my power steering.

So it looks like a minor fix. I will just get it towed locally and have someone tighten the belt.
posted by special-k at 8:21 PM on October 13

Jon-O, I figured as much about the belt, given what he described, but any theories to the brake warning light?
posted by azpenguin at 12:01 AM on October 14

None, actually. I can't imagine that what he drove through was deep enough to flood the master cylinder or infiltrate the brake fluid level sender or anything like that. That'd be a catastrophic situation, and a REALLY deep puddle.
The red BRAKE warning lamp generally only comes on in three situations:
1. Handbrake is applied
2. Brake fluid level is low
3. Low brake system pressure
And I can't imagine how driving through water would cause any of those to occur.
But, y'never know. Stranger things have happened and I can't take a guess about a car that I haven't laid eyes on.
posted by Jon-o at 6:35 AM on October 14

My two guesses:

There's a conductive wear sensor in the break pads that was shorted when the wheel assembly got wet, or

The brake light (erroneously) comes on when the alternator stops spinning (my RX-7 used to do that).
posted by TheNewWazoo at 7:27 AM on October 14

I think it's possible that the brake system warning light could by caused by alternator issues.

OP, is this the "brake" light or the "ABS" light that is coming on? My 99 Impreza has two lights for brake issues, and I'm assuming your Outback does as well. If it was the "ABS" light, it's possible that the puddle might have messed with one or more of the ABS sensors in your wheels. The ABS control unit sits pretty low in the engine bay but that still would have to be a pretty ridiculous puddle.
posted by PFL at 7:37 AM on October 14

It was the brake light, not ABS.
posted by special-k at 7:44 AM on October 14

PS: The puddles were not deep at all. And I drove really slow through all of them.
posted by special-k at 7:47 AM on October 14

sorry, I meant to say not THAT deep.
posted by special-k at 7:48 AM on October 14

There's a conductive wear sensor in the break pads that was shorted when the wheel assembly got wet
I don't think Subaru has that feature. And cars that do will have a seperate pad level warning indicator, rather than turn on the RED BRAKE EMERGENCY OMG light for something that's not yet an emergency.

I'm inclined to think it's a low-voltage/charging system failure side effect, too.
posted by Jon-o at 8:49 AM on October 14

I wouldn't rule out something electrical -- I had a '95 Ford Contour the did nearly the exact same thing -- sometimes intermittently when it was just generally wet out, and sometimes immediately as the result of hitting a puddle.

The fact that it took 45 minutes to get back to normal operation sure sounds like enough time for a connection or wire to dry/drain off.
posted by wrok at 8:55 AM on October 14

The fact that it took 45 minutes to get back to normal operation sure sounds like enough time for a connection or wire to dry/drain off.

It didn't though. I waited 45 min for a ride, and right before I left, I tried it and it still didn't work. Talked to a local mechanic who think it's just the belt. Since the engine is cold, he said that I should have enough maneuverability to get it there (about 1.5 mi). If not I'll get a tow truck.

Going to head over in a few minutes to where I left my car...I'll report back once the mechanic takes a look at it.
posted by special-k at 9:18 AM on October 14

Fixed! I was able to drive the car to the shop (thankfully I had to make only two turns). One serpentine belt was shredded and the other had snapped. Both warning lights are now off and the car is handling well again.

Thanks especially to TheNewWazoo and Jon-O for saving me from the hassle of having this towed quite far away and dealing with the nightmare of retrieving it from there.
posted by special-k at 12:43 PM on October 14

Fantastic!
posted by Jon-o at 3:23 PM on October 14