2G What is this?

[spyderdrifter]

I replaced my fuel filter over the weekend and just looked back through a few pictures I took and noticed a cap. I've never seen this before, but the cap has Prestone printed on it like the coolant brand. Is this some sort of oem coolant drain on the heater core hose that Mitsu ended up removing, or likely something someone added to the system?

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[pauleyman]

https://hardwareonlinestore.com/ind...as&ppcstrkid=1332290283&ppcsu=xhg7f5djqitnahs

 

[IHeartMyHonda]

Looks like someone just added a bleed valve in the heater core hose. Not quite sure why though. Its common on cars that are hard to bleed air pockets from the heater core (Nissan 350z/G35 comes factory with these). Its not hurting anything, but if it bothers you, just put a new hose on it.

 

[chrysler kid]

It is a cooling system flush valve.

You can undo the cap and attach a garden hose to flush the system.

(Though I do sell them to anyone with a jeep 4.0 straight 6 to bleed the heater hoses that go over the motor)

It likely means that your car, like mine, at one point had a stop leak additive added to the cooling system and clogged the heater core.

If I remember correctly you were having problems with the heater on this car when you first bought it.

I fixed the heater on my project car by removing the heater hoses from the engine and flushing the core out from both directions several times with a garden hose. I also replace the heater hoses with new 5/8 universal heater hose.

Recommended for heater core problems:
Blue devil cooling system flush $8
Prestone 5/8 6ft heater hose $8
Prestone/peak coolant flush kit $4 (you need the garden hose attachment)

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