[SupraOfDoom]

I've seen this on a couple of Supra's but I don't get the advantage to it. Though, I'm not very familiar with the item its bypassing.. some sort of coolant pressure regulator or something? It's the coolant hose at the back of the spark plug valley that normal goes to the little grey round cap with a vacuum line on it.

Pictured here:

 

[HypeRev]

The heater control valve? It could be bcuz it’s bad and not letting the heat (water) to go through the core.

 

[DegreE]

You has no heater.

Maybe your heater core is leaking and the previous owner did that because they are a lazy bitch.

 

[SupraOfDoom]

Well it's just a parts car so I was curious. Thanks for the answers.

 

[RazoE]

If I'm remembering correctly, it's a little grey cap between the heater valve and the back of the engine, right..?

I remember when I was NA, coolant would leak through there and drop onto my exhaust manifold and create a smoke fest...

I got rid of that valve and just ran a straight hose, I'm not sure what it does, but it said "prestone" on it, so it couldn't have been stock...

 

[SupraOfDoom]

I've seen this prestone cap 1000000 times on different supra's. One of mine included. I want to know why this is?

Hard to make it out but its here:

 

[DegreE]

wut?

 

[pb92supraturbo]

Prestone flush kit tee - look to the right of the charcoal canister on the firewall.

Doom - Used for hooking up a water hose to aid in flushing the cooling system.

 

[mazzer]

the vsv goes bad ( little white 2-wire connector right where the engine harness goes through the firewall)