Do 2nd gen dodges still circulate coolant through the heater core when it's not in use?

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Nov 29, 2009
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I don't get why I smell a horrible antifreeze smell when the heater is first turned on, but don't smell anything on a warmer day where you would be using the ac. I've also never had to add coolant.
 
Does it have a heater valve in a hose?
If you want to roll the windows down and run the heater for 10 minutes or so to let the smell disipate, it's okay after that, but will go back to smelling the next time you run it. The smell made me sick whatever it was.
 
Do you get water on the floor?

When a/c is on you presumably have the temp blend door closed off to the heater core.
 
Well if it's noticeably worse on "hot" vs "cold" you could still have a leak somewhere.

If defrost tends to cause a film on the inside of the windshield over time this may be further confirmation.
 
2nd generation Dodge what?
What vehicle, year and mileage, please.

I'm fairly certain all vehicles circulate coolant through the heater core.
I believe it's the 'new by-pass' circuit. Gone are the teeny by-pass hoses.
 
2nd generation Dodge what?
What vehicle, year and mileage, please.

I'm fairly certain all vehicles circulate coolant through the heater core.
I believe it's the 'new by-pass' circuit. Gone are the teeny by-pass hoses.
Our current generation Rav4 has a bypass valve in the hose. Apparently they fail all the time and are currently the subject of a class action. They fail open, and give you an annoying warning in the MID, but you can still drive and get heat / AC apparently. Reminds me - I need to get a spare.
 
Bypassing the thermostat, as in older vehicles' layouts?
If a bypass in in the hose...how does it work? Does it close thermally? Is it on a Tee fitting?
Yes - its like the old school ones in the hose. Not entirely sure of the coolant flow. I think there is a bypass that always has coolant flowing, and then the valve opens a second path to the heater core. Its electronically controlled with a positive open valve on a spring - so I suspect when electricity is applied a electromagnet forces it closed - likely for thermal efficiency.

I seem to recall it being the same on the Corolla and the Camry?

The OEM has barbed hoses - no clamps - so you have to replace the whole thing - like the pic. The aftermarket ones have clamped hoses - so if it ever fails again you can replace just the valve - so I will go that route.

There so commonly failing there everywhere on ebay. Here is one example.

https://www.ebay.com/itm/225492481596

1740229512366.webp
 
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