Kind of "Mystery" Coolant leak back of engine (heat exchanger valley leak) (2 Viewers)

[linuxgod]

Actually, I thought the knock sensors were no problem. The one I ended up breaking and having to re-pin was the one on the throttle body housing. New item by Mark Feferman - https://photos.app.goo.gl/u2sLy7Y65pzH691F9

Mice tend to chew on the knock sensor harness wires for some reason. Ask me how I know. Not you will necessarily need one, but don’t be shocked if yours has been compromised when taking things apart

 

[muzzam]

Oh, you might consider ordering a 82219-60090 wiring harness. This is the harness for the 4 knock sensors. If you are going to break any clips during this job, it will most likely be on this harness. Don't technically need it, but it falls victim to broken clips and rodents pretty regularly.

I'm currently in the middle of this job and have had my intake manifold off a few times recently, so it's pretty fresh in my head. I assume there are some well written guides already posted.

Noted. Thanks

Actually, I thought the knock sensors were no problem. The one I ended up breaking and having to re-pin was the one on the throttle body housing. New item by Mark Feferman - https://photos.app.goo.gl/u2sLy7Y65pzH691F9

Thanks guys. Will keep it handy as well.

 

[golfer2000]

Are there any detailed videos of doing this on the 200 series? It seems like most are from the isf, GX, Tundra, etc.

 

[mfeferman]

Are there any detailed videos of doing this on the 200 series? It seems like most are from the isf, GX, Tundra, etc.

It’s very straightforward. Just time consuming.

 

[Wah00]

I'm about to pull the trigger on a 2019 200 for Mrs. Wah00.

She's been driving a 2012 Sequoia, and we dealt with the valley leak problem with it.

I've searched the forum and can't seem to find if this issue was resolved at any point by Toyota, or if the newer 5.7s (including the 2019 ...) will also be subject to the need for this repair. Any help appreciated.

 

[gray rider]

easy repair...

 

[gray rider]

Les Paul gold top guitar as well!

 

[PDoyle]

Thought the valley plate leak was limited to 2014 and below?

 

[Acrad]

IMO.. I don’t think I would rule out any model year without enough time, heat cycles and mileage

 

[bloc]

IMO.. I don’t think I would rule out any model year without enough time, heat cycles and mileage

This

 

[Supra88]

IMO.. I don’t think I would rule out any model year without enough time, heat cycles and mileage

It's not a matter of if, it's when it will happen.

 

[bloc]

I dislike absolutes. The odds of there not being a single 3UR valley plate that went the life of the rest of the engine without leaking must be very low.

Yes, it's common. But some of us are accruing significant mileage without that failure. I'm at 225k without a hint of a leak.

Edit: it's also not like these fail catastrophically, which would help make the case for doing the job as PM. Owners should just monitor coolant level and address it if it comes up.

 

[PDoyle]

The bright side is, it's not a vehicle with many other major issues.

 

[gasman4u]

? for the mods - is there a consolidated thread for where common oil/coolant leaks are for the 5.7 and where/what to look for? If not, maybe an opportunity for the “start here” thread