Help: Catastrophic Engine Failure 5.7L V8

Looking for help in finding a Toyota 5.7L engine designer\engineer or technician who has knows how these 5.7L V8 engines are designed to perform\fail when a knock sensor becomes disconnected from engine (rat chewed wire). Vehicle year is 2011. Long story short, knock sensor code error thrown for once side, dealer said it was safe to drive vehicle 150 miles home, electrocuted dead rat found under exhaust manifold with chewed up knock sensor wire. Knock sensor replaced, vehicle started and 2 holes immediately were blown in engine - one of each side of engine - rear cylinder near transmission. Dealer technicians do not have experience with catastrophic engine failures, dealer is trying to blame us for the failure, when it is clearly not our fault. Toyota customer care refuses to send issue onto the toyota plant where these engines are designed and made in the US. Need to know if anyone has ever seen this happen before. I know earlier 2nd gen engines had metallurgical defects and rods punched thru the side wall. Here, same case, rods severed and large hole on both sides of engine. See pics. Problem is, the metallurgical issue with the camshaft was supposed to have been solved in previous years so Toyota doesn't want to investigate as this could seriously lead to major recalls or class action lawsuits. Please help!!!

 

dang thats crazy

 

The dealer owes you an engine. If they refuse, take them to court.

 

Engine go boom, it happens. Rod broke and tried to play peek-a-boo everywhere it could. Doubt it has anything to do with the 07 metallurgical camshaft failure. Knock system goes safe by default, but anything is possible.

 

IMO, knock sensor problem is unrelated to this failure. Failures from faulty knock sensors would occur over a longer period of time, and on a smaller scale. Engines don't just explode, regardless of what octane gasoline you're using. But, I would believe exceeding the red-line could cause an engine to explode.

Where did the failure occur? If it occurred in the dealer's shop, he owes you an engine.

 

Blew my 4.0L inline 6 on a Jeep XJ, but havent heard of anything like this.

 

Bouncing off the rev limiter.......maybe. Just by starting the engine.....never seen it.

 

@ViktorG Any thoughts for OP?

 

If you have full coverage insurance they will pay for all of it since the initial wire harness issue was caused by mouse damage.

 

when a knock sensor fault code is set, the ECM will set ignition timing to maximum retard as a fail safe. This will reduce engine power, I can’t see how that would be connected to the failure your engine experienced.

 

Yea. Soo to get to the knock sensors the plenum has to come off... did someone happen to drop anything down the intake when it was being worked on?? Engines don’t just throw rods when started up.. after 7 years of working at a Toyota dealer, I’ve yet to have a 5.7 come in with a failure that wasn’t created by someone doing a repair wrong. And the 2 I’ve replaced were due to timing chains being installed incorrectly and valves touching pistons.. never seen one throw a rod. Let alone on first start up

 

What I'm talking about. It takes an incredible amount of kinetic energy to blow the engine internals THROUGH the cylinder case, meaning the rotating/reciprocating parts inside had to be moving VERY FAST.

 

12VDC max electrocutes a rat, tough to imagine that.

 

I would second what @graysquirrel said initially.. Make some noise, my coworker got taken advantage by some predatory company years ago, and she went to the local news and created a very uncomfortable environment for the company. She got what she wanted, plus some... I forget what exactly it was. but it appeared it worked..

 

Engine likely ingested debris.

Edit

It looks like a piston or connecting rod broke.

A knock sensor failure will not cause that damage instantaneously.

If the knock sensors are under the intake then its almost 100% that a bolt, fastener, etc fell into the intake manifold.

 

Rat must have been riding a wrench that fell across the starter terminals.

 

Man, I am all for justice and dealers
can be iffy, but how does a rat problem become a dealer or Toyota responsibility?

This is obviously a rare occurrence on a 5.7, let alone any make or model of current truck. But how would any mechanic foresee a catastrophic failure if you drove home?
-Running with 4 broken lug nuts, maybe.
-hole in the oil pan, maybe.
-blown radiator hose, maybe.


I mean , yeah it’s bad advice,
A coincidence, or just unlucky occurrence.

I hope the dealer says, “hey buddy let us help you out and make you a good deal on an agreeable resolve.” I truly do. And it sucks with a broken vehicle and I feel for you.
But ultimately was it a rodent, bad repair job, history with a decade old vehicle? Who knows? Hard to prove.

 

The early camshaft issue was indeed fixed. Was caught early. Over 100,000 Tundras were built in 07. The camshaft affected less than 2 dozen Tundras. 14 years ago. Just sayin.

 

More to the story?

 

This^^^^^

 

Looks like the chain of events were:

knock sensor failure from rodent.
Truck taken to dealer.
Knock sensor replaced.
Engine destroyed on start up.

I bet the story and plot thickens--OP you need to get inside the engine to see if there is signs of a bolt that fell into the intake. Look for a heavily damaged bolt in the oil pan or possibly stuck in piston top. There could even be witness marks on top of piston of threads from fastener. The cylinder heads will also look like it has heavy shot-peen type of damage.

 

Dealer worked on engine.
Dealer said you’re good to go.
Engine grenades upon startup.

How is the dealer not liable here?

Best advice so far is from @blanchard7684 to look for what the service tech dropped into the intake. Could it be the old sensor or some of the wiring even?

 

The forensics should be done, but I'm skeptical a foreign object dropped into the intake could be the sole cause of that much damage. Something else was also involved. Damage from valve or valve seat dropping directly into the cylinder (worst case?) is often repairable, even if it means a full rebuild with oversize pistons. Probably not the most cost-effective choice.

 

When I was a full time mechanic years ago...This exact scenario happened to me and I'll never forget it. Worst mistake I ever made as a mechanic. I had to pay for the repairs out of pocket.

I did an injector replacement on a Chevy 3.1. It was Friday and my mind was on getting out of work early.

I had ordered the injectors based off a previous diagnosis of a leaking injector. Customer was an older lady. The 3.1 had 190,000 miles on it. She needed to get it down the road a bit more. I scheduled her to bring car back once I got injectors in.

It was stupid simple job. I got the upper half of intake off. pulled the injector rails. swapped the injectors and o-rings. replaced the rails. cycled the key to check for leaks. good to go.

I didn't realize in the process of doing this one or more injector bolts dropped through the injector port into the lower intake port. I didn't use a magnetic tray for the bolts.

I reinstalled the injector rail and had to hunt for two bolts that were missing. lol...duh...wow. reinstalled upper intake.

Well I found the bolts later...stuck in cylinder head and piston.

When I started the car it clattered like utter hell. Thinking I didn't make a huge mistake, and that it was carbon flaking off on a 190000 mile engine, I let it run...then it stopped.

The whole engine had damage. I didn't window the block, but:

2 pistons were broke in pieces. I found remnants of the bolt pressed in to one.
2 broke connecting rods.
crankshaft damaged from overload.
One cylinder head was toast.
Cylinder damage was extensive but barely salvageable.

I still to this day about 20 years later have the mangled bolt I dropped in the engine as a morbid memento.

I got sweaty palms reading this incident from the OP. I was in the tech's shoes.

I fessed up to the shop manager. He was pissed. But I offered to pay for everything out of pocket and work round the clock until car is repaired.

I even fixed other things as I saw them...radiator, water pump, etc...all out of pocket.

lesson learned for me: you'd be amazed at what a small fastener can do when it is in an engine going over 1000 rpm.

EDIT:

I have windowed a block unexpectedly...A friend needed help getting a Ford 7.3 non turbo diesel started.

I didn't realize it had a massive head gasket issue. Niether did my friend. He just bought it.

We got it to turn over. After several ether sprays it started. It quickly began rattling. Then almost thundering. Then we saw smoke.

Block was windowed. We tore it down for parts and found the huge head gasket leak that put water in multiple cylinders.

This was out in a field in the middle of nowhere. We didn't notice until later the area around the exhaust pipe was muddy...lol..

 

It takes less than 1/2 of an amp to kill a person, doesn’t matter if that amp is generated from ac or dc power.

Edit: Apparently dc is considered safer due to impedance. But my point is that it doesn’t take much amperage to be killed or seriously injured and so I imagine for a rat it could happen.

 

I interpreted the write up differently. To me it sounded like a chewed wire replaced.
But yeah , you’re right. If the whole top was pulled off for sensor and harness, it’s be hard to think some debris wasn’t lost in there.
I’d assume they’d would have ran it, run diagnostics and test drive. Maybe I give them to much credit.

 

I had something similar happen to a Jeep 4.0. I was replacing exhaust manifold, and if I recall correctly, intake had to come off for some reason (maybe accessibility to bolts? It's been a while...). Anyway, I didn't get the gasket set correctly in the intake when I reinstalled it. On startup the engine immediately revved uncntrolled. Fortunately the 4.0 doesn't rev fast, and I cut it off immeduately, maybe hitting 4000 rpm. Googled the issue, got the gasket to seal properly and never had another issue. Until 20,000 miles later when it broke a piston skirt. Related? I don't know. I think the piston slap was there before I did the repair - it was just masked by the leaky, noisy exhaust manifold.

Wonder if something similar happened here, only they didn't cut ignition soon enough to prevent over-revving it?

 

Ouch...sorry you are going through this. Hopefully the dealer steps up...

 

Who did the work? If your engine didn’t have holes in it before the repair and now has a couple of holes in it after the repair, I kinda feel like whoever did the work should be responsible.

 

I'm sorry to hear about your misfortune. That really sucks man!

This statement does not indicate WHO replaced the knock sensor. As far as I'm interpreting it, OP contacted the dealer on the phone, then drove the truck home. Next statement says there was a dead rat found. By whom, OP or the dealer? Then, sensor is replaced, the truck is started, and engine immediately grenaded itself.

Need clarification

Again, where did the engine blow, at the dealership, after they worked on it? Yeah, I'd say they owe you an engine. Or, was it in your garage?