Coolant leak, Bypass Blown heater core?



Hi Folks,

Longtime listener, first time posting…

A friend of mine has a 2000 Dodge Caravan, he blew out his heater core yesterday, and got an estimate of $2k to fix it, which is way more than he can afford. He needs his car for work and still has payments on it…

He thinks the damage was caused by him burning rubber struggling to get up an icy hill yesterday

The coolant is leaking from under the car, not in the interior - perhaps the diagnosis is incorrect?

Back in the old days it would be possible to bypass the heater core and just keep the coolant circulating thru the engine. Is it still possible to do this in newer cars, or would that cause problems with sensors etc…

Also we’re in New England, so presumably this “fix” would disable heat and defrost functions. Could he plug a small space heater into the lighter socket or does that draw too much current?

Thanks in advance for your advice!

Dunadan, friend of a driver in need


The heater core can be bypassed, but of course there will be no heating or defrosting. A 120 volt space heater powered through an inverter will draw way too much power and blow the fuse for the socket, so this is not an alternative. I have seen small units that plug into the lighter socket that have a fan and heating coil. They don’t produce much heat, but if placed on the dashboard may clear a little bit of the windshield, but it would be a very little bit.

The diagnosis may be correct as the coolant is probably draining through the condensate line that the evaporator for the air conditioning uses as the heater core and evaporator are in the same chamber.

$2000 seems a little high for a heater core although this is a labor intensive job. The evaporator for the air conditioning may have to be moved necessitating discharging the air conditioning system. Some communities have radiator and air conditioning shops that have done many of these jobs and may give a better price.


Thanks for the comments! I just heard from my friend, he took it to another mechanic and it looks like a blown hose rather than the heater core, much cheaper price, about $600.
I am hoping he’s all set now.

Thanks for your time :slight_smile: