Engine coolant inside catalytic converter

Which Catalytic Converter? There are 2 (TWC in the diagram). Did they indicate how it was getting there?



Clutching at straws - maybe the Exhaust Heat Recirculation System ... BUT ...

The odd thing is - the Exhaust Heat Recirculation System (on some USA and Canadian Models - maybe other cooler climes too) which has coolant circulated to it - is AFTER the TWC (Two Way Catalytic Converter).





[Note that the white arrows indicate COOLANT, black arrows indicate EXHAUST GAS]




No - I don't know, sorry. We don't have the Exhaust Heat Recirculation System here.

 

I'm going to be watching this thread, primarily for my own edification, since I know little about this system, other than its mere existence. I understand it is, in effect, the "replacement" for the "Thermos" system which we had in the Gen-2 cars?

That said (and asked), the first thing that comes to mind is how on earth any coolant, if it had leaked out from the liquid/coolant side of the heat exchanger, would "survive" as identifiable coolant for any appreciable time in any other part of the exhaust, pipes or especially the cat?!? I would think that it would either boil or burn off almost immediately, given the temperature levels involved. What am i missing (other than a few assorted loose screws...)?

 

Thanks - I knew about that video but couldn't spot it in a hurry (I was expecting visitors who've gone now).

The engine coolant being empty won't always trigger the Check Engine Light. Though in modern computer monitored cars, I'd hope there was some way to get it to light.

It's never happened to me, but my Dad twice warped the head on vehicles - both times, there had been a catastrophic loss of coolant (first time dealership didn't tighten a hose after service - and it stopped 7 minutes later when it blew off - 2nd time more routine). But the coolant disappeared so quickly that the temperature gauge never went high - as there was no coolant to heat it. The cars just stopped both times.

Hope the repair is quick - good they've given you a loan car.

 

You maybe having a failed cylinder head gasket, or one of the loops of the cooling system is leaking into the exhaust system.
In this case, I bet you should see white vapour from your exhaust tail pipe when the ICE runs.

 

I'm thinking they have a TSB out on this leak.

 

I have yet to see or hear of a TSB on this issue. You may have read it on here from other owners with the issue, as I remember a thread or two on it as well, but no recall.

 

The Cat is the box in front of the heat exchanger, the coolant will have leaked into the heat exchanger, vapourised then condensed further back in the exhaust, where they probably stuck the camera.
It looks like the front exhaust is all one piece from the manifold, incorporating the cat, the heat exchanger and the central (sub) muffler, with a joint to the back half, which is separate.

 

There's a ball-joint between the 2 Catalytic Converters - not sure if it separates? Though this diagram sort-of implies it might:

 

Where is the 2nd cat, I can only see 1 ?
There is a ball joint at the front of the exhaust, joining it to the manifold (not on the diagram) and a ball joint at the joint between the front half of the exhaust and the back half, both labelled "a*" in the diagram, there isn't a cat in front of the first joint (manifold) and there isn't a cat behind the second joint to the back half of the exhaust, only a big muffler at the back end.

 

Check out the more complete diagram in the #2 post in the thread. The first cat (TWC) is essentially immediately downstream of the confluence of the exhaust manifold; the second is maybe 12-16 inches further downstream, and appears just before the heat exchanger device.

 

Any idea how to tell which USA models? Probably a good idea to keep an eye on the engine coolant reservoir...

 

Awww, c'mon -- coolant hoses in close proximity to catalytic converters -- what could possibly go wrong. . .?

 

Seriously though, I'm a bit perplexed at the suggestion I too have noticed that not all the cars have this "feature." If it's largely an emissions control measure, for quick engine heating to "clean running" temps, then I'd expect all cars to be so equipped, just like all the Gen-2 cars had the so-called Thermos, for just this same reason.

EDIT: It's not as if people never move their homes from warmer climates to colder ones. If so, then what? You drive a "dirty," slow to warm-up Prius from then on???

 

Same diagram ?
It goes, manifold joint, oxygen sensor, cat, heat exchanger (not a cat), secondary muffler, ball joint, rear exhaust.