E30 coolant leak into interior...heater core or?

[WaffleMan]

I just found that all the work I had done the previous week ripping out the carpet and extra plasticy bits for my track car was actually just making it easier to spot a leaking...something.

I noticed a good size puddle today when I got it, drove it for about an hour and the puddle got bigger. So I took a look at the heater core, nothing below it seemed wet and I couldnt see any leaks.

The only place I could really see any drippage at all was at the top of the plastic heater core tubes that goes through the firewall, the little white thing with a single wire that I only have guesses as to what it is.

Is there a reason to suspect its leaking anywere else or should I just replace (unknown white sensor?)

Thanks guys

Attached a picture, you can even see a little bit of coolant still there

[thejlevie]

That "little white thing with a single wire" is the heater valve. It, or the o-rings at either end of the tube, could be leaking.

[SWISS]

Heater vavle sh1t the bed. The car in my sig FS had the same problem on pick up. Temp fix- Re route heater hoses. Long term order a new one ( comes with pipe) or scavenge from the sally. I bought a used one at LKQ for $.79 no bs

[WaffleMan]

im surprised a new heater core would have been cheaper than the pipe/valve combo. Since im gutting it for a track car I might just bypass the core and leave it. I live in california so heat isnt a huge need. (plus thats some extra weight to shed)

[thejlevie]

If this is a track car, plug the end of each of the heater hoses. Do not loop the hoses as that will cause part of the coolant flow to bypass the radiator.

[ddavidv]

Ditch the heater core and it's related plumbery. I tried a used core in mine and it lasted less than a year. Those things are made of FAIL and new ones are too expensive to justify for a race car.

[SWISS]

If this is a track car, plug the end of each of the heater hoses. Do not loop the hoses as that will cause part of the coolant flow to bypass the radiator.

Isn't the heater core circuit itself a loop....

OP I drove my E30 from Savannah,GA to Tulsa,OK straight re routing the factory hoses at the firewall. Never got over the middle of the gauge once.

[thejlevie]

Isn't the heater core circuit itself a loop....

It is, but there's a valve in the middle of the loop that shuts off flow when the heater isn't being used. The heater flow short circuits from the front to the rear of the block so that full heat is available regardless of the state of the thermostat. If you loop the hoses that flow occurs all the time and coolant flowing through that loop isn't going through the radiator.

[SWISS]

It is, but there's a valve in the middle of the loop that shuts off flow when the heater isn't being used. The heater flow short circuits from the front to the rear of the block so that full heat is available regardless of the state of the thermostat. If you loop the hoses that flow occurs all the time and coolant flowing through that loop isn't going through the radiator.

I think you're wrong or off a bit on this one.
The hose on the back of head flows hot water to the core and it comes out the firewall into the spider hose where it can go 2 ways, flow back straight into the therm housing and into the upper rad to be cooled and sucked back up to the block from the WP, or overflow in the res. Making the circuit smaller by eliminating the core is a continuous loop and should incite flow by removing excess fluid travel and restriction.

[thejlevie]

The return flow from the heater core goes to the pump intake so the car can produce heat when the thermostat is closed.

[WaffleMan]

So is the upper hose going into the heater core the flow in or out?
Swiss I think i get what your saying, ive looked at it and to bypass I pretty much just remove the upperhose connecting into the firewall and then use the lowerhose to replace it and complete the loop?