2012 Sienna Hydrolocked Engine

missmy06

Has anyone ever had their 2011+ Sienna engine hydrolock after driving through heavy rain? It happened to my wife recently with our 1-week old 2012 Sienna with just 400 mile on the odo. Googled the topic and found a discussion on another site. It happened to two others within this year. One in San Fransisco in Feb/2012 and another in Miami in May/2012. Hydrolock is when the engne sucks in water and dies. Stuff bends inside and ruins the engine. It's not covered under the new car warranty. The 2012 Sienna air intake is up front and, in my opinion, seems prone to suck in every drop of rain splash that gets near it.

fibber2

New name, same wife? Just kidding. I'm here to haunt you.

To bring everyone up to speed, I did some comparisons on the air intact tract & air cleaner box on the 2GR-FE engine as used in the Gen-2 (2007-2010) Sienna verses the same engine as installed on the Gen-3 vans.

The newer models appear like they could be more prone to channeling water that might make it up under the hood front lip to the engine. Low spots, routing, resonator chamber placement, size and positioning of the air cleaner box & filter on the older models look to provide plenty of opportunity for separation (water to drop out and drain away).

missmy06

Yep, same guy. I thought it was fitting after so much has been said and done. Bought an '06 Sienna, certified used back in '09. Had it for three years, no issues. Loved Toyota, bought a new one, dead in a week, the love is gone. I miss my 06 Sienna.

fibber2

Your 3MZ engine (2004-2006) uses the same design as the later Gen-2 (not unexpected being the same engine bay), so my commentary on layout applies.

missmy06

Wow, fibber2, you know more about these engines than I will ever. Do you know if the Avalon shares the same air intake design as the Sienna?

fibber2

Looking into my crystal ball and saying along with Bullwinkle: "Eenie meenie chili beanie, the spirits are about to speak."

You are just too easily impressed! Part of good engineering practice is a strong reliance on research - both original and prior art. Stated another way - I'm really really really good at looking things up!!

So, just for fun, I went looking for information on the Air Cleaner Assembly for the 2006 Avalon (as that matches the year of your old Sienna), and voila, it shares almost every single part!

missmy06

Lol. How about the current gen Avalon? Do you think it shares the Air Cleaner Assy of the 3rd gen Sienna?

fibber2

I met with "Deep Throut" in the parking garage earlier in the evening. Along with more secrets about 'Tricky Dick', he revealed to me that the 2011 Avalon (no info available on the 2012) shares the same design as the 2006.

ateixeira

I've heard of a couple of cases of hydrolock before, but both happened off road while crossing water.

Do you think it's possible she ran over a large puddle or standing water?

missmy06

Both. She said there were puddles on the main roads that she drove over on her way back home. And there was standing water in some areas when she entered our subdivision. Our subdivision isn't flat so there were areas that appeared to be deeper that she avoided and areas that had no standing water. Based on her description, I imagine she drove through approx 6" standing water at 5-10mph when the engine stalled.

ateixeira

Probably doesn't take much water to do damage. Compression ratios run around 10 to 1, and water doesn't compress.

Bet it threw a rod or something.

fibber2

The height of the chin spoiler is likely the culprit that induced a wave that forced water up and into the grill. Actually over the grill as the intake is on top of the radiator upper support. If the spoiler cleared the water, I cannot see any way that tire action could possibly do this. Tire splash tends to go out to the side. Not sure on the new models, but on my '08 the lowest spot is around 6-7" off the ground. The water would have to be a few inches above that to create the 'snow plow' wave to force it vertically. I'd guess, and just a guess depending on speed that 10" could do it?

The only other scenario would be a vehicle coming from the other direction at sufficient speed. Tire splash from another vehicle has more than once sent water onto my windshield from hitting standing water of only a few inches.

missmy06

Well there were other vehicles driving in the sub along with my wife. But because of the heavy rain none were going fast. My wife's Sienna stalled right after she turned onto a street and she estimates she was doing 5-10mph at most. Other cars driving past were probably doing similar speeds. But she did note that there was splash from both her van and the other cars going by. And I guess in some respect I should feel lucky because it happened in our sub and everyone was going too slow to cause any crashes. Had it happened on the main road with faster speeds it could have turned out much worse. And had we been on vacation and out of town on unfamiliar roads it could have been worse yet. As for the damage, the dealer has yet to tell me what all happened inside the engine. They told my insurance adjuster that they could manually rotate the engine "backward but not forward". One other bit of luck is that my insurance (Liberty) has approved all the repairs that the dealer said they'd need to do to bring our one week old van back to new condition. And that's with all new parts, not aftermarket. And Toyota said that the engine would be certifiable since the repair is done by a dealer using new parts. I'm hoping that will help with the resale value down the road.

What I find disappointing in all this is that Toyota had a robust design on the 2nd generation Sienna but chose to go with a more vulnerable design on the new Sienna. All at the customer's expense.

missmy06

You make a good point, fibber2, about the chin spoiler. On our van the chin spoiler, if I am thinking of the correct part, had separated from the front bumper on the right side. From what I recall the intake is on the left side of the van but maybe a half-way dragging chin spoiler channeled more water up into the vicinity of the intake.