Water leak...into spare tire area etc

I just picked up a 2008 and it probably had something like yours happen or at least the previous people tried to fix the leak since there is new seam sealer around all the seams of the trunk. I seam sealed the usual spots around the top of the hatch but still had a leak. I found one seam below the right tail light just behind the bumper where there was little sealer and it had split. That was where the majority of it was coming in. The rubber gaskets on the tail light side of the bolts were also shot so I replaced those too. Waiting another 15 minutes to try the water test again.

I have nothing to complain about, it is a 2008 with 120k on it for $5k and a three year, unlimited mile warranty on the hybrid battery from a local one man dealer that we (my daughter) have bought two other cars from. The others were a Sienna and a Hybrid Camry. Both in great shape for a good price.

 

After sealing those two on each side my trunk is now bone dry. I didn't see this area anywhere else on the web.

 

Thanks for posting the fix for your problem, it may help others out in the future now that it is documented.

 

Did it work?

 

I’ve used the sealant mentioned before, and it’s still dry as a bone.

 

Hi Don I have the same exact leak on my 2008 prius and I also sealed all the roof rail common leak places. did the taillight seal fix the problem? did you find the source?

Eluo, good thinking, but this is not the problem. I had my son hose water over the tailgate while I was sitting inside the trunk and I saw water seeping in the same location as Don. your problem happens only when the car is moving and if you are missing the fender piece.

 

I had a guy that does body work take a look and he thinks I need to replace the foam gasket behind the headlights and behind the bumper.

What would you get from Home Depot for making the gasket?

 

I bought a ebay rear tail light assy and it leaked really bad along the bottom edge. I bet the body shop bought cheapies and not the oems.

 

I just found water in my spare tire well after getting a flat.

No noticeable smells from standing water, but there was probably an inch of water in there.

Been rainy here lately and I also just recently replaced the hatch struts. New ones are very strong and the hatch will come to a violent stop on full open if you don't hold it. I believe I may have the issues others have found with the body seems under the roof rain gutters opening up. Will post results of sealing these when I get to it.

 

Take battery out there’s a rubber plug in the bottom of the well

If car lives outside just drill a weep hole through it if garaged like mine just take the plug out.

Same for the under the spare tire.

If car lives outside check the cabin air filer for mice activity.

 

First time ever, found water in wheel well and below the 12v a couple of weeks ago. Pulled the two plugs and let the areas dry while I caulked everything up and down the channels. Not a pretty job. I have trouble holding my right hand steady since an accident a year ago, but, even though it looks somewhat chunky and choppy, it should seal O.K. Have not checked to see if it worked, yet.

Oh, and I KNOW the leak must be of recent origin, as I had to use the spare about 45 days ago, and there was NO water in wheel well and it had been raining here pretty hard and pretty steady for weeks at that time.

Anyway, getting those plugs out is the big thing.

You actually do not need to take the battery out, you can access the plug from under the car. Just make sure not to touch the exhaust system if it is at all warm. A needle-nose ViseGrip and a small flathead screwdriver helped on that task.

 

So here's my story, probably not many people look at these anymore. About 3 weeks or so ago, I went to a local used car lot to purchase a 2004 Toyota Corolla. When I got there, they said, well someone's already put a down payment on that one, but we've got some other ones in your price range. I ended up settling on a 2009 Prius. It's my first hybrid and also the first time I've ever went to an actual car lot to purchase a vehicle, I've always either bought from an individual person or when I was a teenager, my dad bought me cars and I would pay him the money for the loan. SO, needless to say, I think I've been swindled. I noticed it was making an audible sound and it didn't sound bad, but like something was kicking on and off periodically when it shouldn't be, sort of a mechanical whirring sound that repeats every minute or so. From what I've read on other forum posts, I'm concerned it may be the brake actuator...but, I digress. The car had been driving fine other than that, no issues - except we got a few warning lights, various ones. The check engine, ABS, brake, VSBC all came on - again leading me to the possible brake actuator issue - we've reset them and so far they haven't come back. But then, suddenly, I went to go get in my car on my lunch break and tried to start it, and all the lights flashed (including the red triangle of death) and it refused to start. After that, I tried it two or three more times - it just wouldn't do anything. No lights, no way to get it to Ready, no dash lights, head lights, nothing. So I figured, well maybe it's the 12v battery - again, after reading other posts, thinking it probably just needed to be replaced. My boyfriend managed to get a new one for a decent price...but when he pulled everything out from the trunk area to replace the battery, he found something interesting (and scary). Pooled water where the spare tire well is, and pooled water where the battery is!!! I have owned many, many older cars in my life, but have never seen anything like that in my life. He also noticed that you could hear liquid sloshing around in the battery - he said maybe it could be water, too? But not sure. AND, clearly the previous owner had had an issue with it, because you can see some sort of seal (it actually looks like weld, but I'm not an expert) all around the spare tire area, plus around where the battery is, you can see what looks like some other type of sealant - possibly even wood glue, as it was a dingy brown-yellowish color, but we're not sure either. This was one area we did not think to check when we bought the car, but I did notice there was a slight mustiness in the car and chalked it up to it sitting on the dealer's lot for a while before we bought it. I was concerned enough as it was with the possibly brake actuator problem, but this...this is a new one for me. I'm at a loss. Other than this issue, the car is a dream to drive - the suspension is in great shape and it just glides around, I like the back-up camera, I'm happy with everything else so far. The motor seems to be in good shape, it's just stupid to me that something like this could be an issue. I think Toyota should do a recall, as there is no easy way to fix this. Luckily, I work with a girl who's boyfriend welds, so I may be able to get him to touch up any hairline cracks in the body welds, and if there are other problematic areas, I was thinking about using some sealant available to me for free here at work, it's called Solar Seal and it's a 25-year terpolymer sealant used typically when our techs do repairs to houses because of damage from nuisance wildlife. Either way, I'm pretty upset. I hope I don't have to resort to pulling out the spare tire and the battery just to mop up standing water every so often. And of course (just my luck), we're expecting heavy storms here in my city in the next few days. I just feel like I'm doomed to always have problems with cars like this, I can't afford to pay $300 - $500 a month to buy a brand new car or one with a warranty. And I can't afford to be without a car entirely, even though I live about a half mile from where I work and used to take the bus every day. It's just so frustrating - I specifically wanted to buy a Toyota because I've had multiple GM cars with serious issues (Oldsmobile Aurora - bad seals in the motor causing blown repeated blown head gaskets / manifold intake gaskets, cavaliers with same issue with head gaskets blowing, etc.) I thought Toyota would be manufactured better. I understand welds will eventually fail but I've never, ever seen it happen in a car? do not know. Just wanted to share my story - maybe I can successfully find the problem area and seal it well enough to prevent this from happening again.

 

Nothing unusual for a GEN II Prius. I will admit, I did not read your entire post, because being one big block of copy without any paragraphs was a bit daunting.

You basically need to pull the plugs in the spare compartment, as well as the one under the battery to let water drain out.

You need to open the hatch and seal all along,,,,several threads on here about how to do it, as well as a lot of YouTube vids.

No big deal. You did not get cheated, as far I can tell.

 

Mine leaked like that, too. Turned out the ingress was from where left side roof panel met left side rear body panel - under the trim piece, the seal was cracked. Sealed it and no more leaks. For sure drain the water. do not know about the noises and check-lights.

 

Crazy, a lot of people with similar issue....

My wheel well always had water in it. Didn't know why.

I removed everything and got someone to spray a hose over the hatch. I saw water pouring in from two cracks on either side of the interior metal frame.

Could have been from an accident from the original owner. Either way, the water would stay in the car, and actually get splashed up while driving to the point it went under the batteries and soaked the back seat floor mats.

I sealed the cracks from the outside with a certain type of metal, waterproof and malleable epoxy. I haven't had any issue since.

The car did smell horrible though, and I thought it would eventually dry out by leaving the windows open often. But almost 6 months later, it was still the same. I had to use some odor eliminator chemical. That seems to do the trick.

I heard of other people reporting cracks towards the roof in the roof well area. That wasn't the case for me. I had to rip out the interior paneling to expose the metal and see the water come pouring in to find out.

 

Very common g2 issue.

The battery well has a rubber plug in it for this very reason and there’s one under the spare tire too.

If you garage the car every day your u can remove those plugs.. if you don’t you make the car very susceptible to mouse infestation which is a big problem With a Prius as they find the cars wiring very delicious.

If you don’t garage the car just drill a small 1/4 inch drip hole in both plugs for the water to drip out.

The leaks are from cracks where the quarter panel meets the roof very high stress area there as that’s the body well/body putty spot as you constantly slam the hatch and cracks get in that valley.from that.. You can pop the black plastic rails that are on the roof and see what I mean.

If you don’t discover the water quickly not sure why as it will stink it will ingress to under the carpet in the back seat floor and really stink up the car.

 

Hi Peter,

Congratulations on locating the source of the leak(s) and repairing them successfully.

Another trick I read here is to shut the car up in the sun and run a dehumidifier together with an ozone generator aimed at the air intake of the A/C (have the A/c running) on recirc.

But good job on the repair.

 

I made a quick post about how I sealed my roof cracks with a $5 tube of caulk from True Value. No more water in the trunk thankfully!

 

So many places to seal these Gen2 cars from water as they age...

While many of you have had luck sealing things, I only managed to slow the rate of leakage and finally gave up and punched some small holes in the back:
1. driver's side behind rear wheel well
2. spare tire well, through rubber stoppers (made it a little larger so the rubber did not close back up)
3. passenger side behind rear wheel well (battery well)

For the 2 holes behind the real wheel wells I drilled near the lowest, most forward spot so as water will migrate foward under braking. In the spare tire area I just drilled through the forward rubber stopper, but made the hole a bit larger.

This car had a minor rear-end impact after my initial exploration and there are just too many places that water can get in.

A word about the ODOR some people experience after water leaks into the back... When I was tearing the back apart, I found a ton of little mold spots under and behind the "carpet" panels (around wheel wells and up to the rear seat area). Best to check for this and clean it as best as possible. I sprayed the back-side of these carpet panels with a moldicide and left them laying in the hot sun for a week to help kill as much of the mold spores as possible.

Before I had time to do a thorough tear-down, if the car had not recently been driven I would open all the doors for a few seconds before getting in, and then open all windows for the first few minutes driving at speed to clear the air a bit. Not a good thing to breathe mold in concentrated volumes.

 

Using your photo to highlight one of the 2 screws with large black collars at the top of the bumper panel, just below the hatchback opening. When the screws are removed you will see green plastic pieces stuck in the hole. In theory, the water running down each side under the hatchback dumps straight down and away from these screws, but I noticed corrosion trails that seemed to lead to these spots, so I pulled the screw and pried the bumper panel away (like in hoosier8's photo above), cleaned it and added sealant around the green plastic and then a bit inside the hole before restoring everything.

Another tip: When I pulled everything apart and removed the taillight assemblies, I got rid of the crappy thin, foam washers and replaced them with rubber grommets (look like black, soft rubber doughnuts that have a slice round the outside). I found a size that slotted perfectly into the holes so that when I reattached each taillight, the grommet would compress to help keep water out.