Coolant Leak From Heater Core on Chevrolet S10

The heater core under the right side of the dashboard may leak engine coolant which can puddle on the passenger front floor. The loss of coolant may cause an engine overheating condition. Our technicians tell us that removal of the dash board is necessary to replace the heater on these vehicles.

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Average mileage: 150,551 (13,200–270,000)
14 model years affected: 1990, 1991, 1992, 1993, more1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003
64 people reported this problem
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Viewing 1 - 20 of 30 problem details
need to replace heater core some have said this model you dont have to remove entire dash
I had this too, had to pull out dash and change out heater core, about two days work, plus every time the heater was turned on it smelled like antifreeze inside the cab, that lasted more than a year.
1996 Chevrolet S10 256,310 mi,
Strong smell of antifreeze coming from vents when i turn up blower motor
2 dash mount screws on right lower, radio out for ease of core case screws,ease dash slightly out, plenty of room,under 2 hrs, easy, cetronia auto allentown pa
1990 Chevrolet S10 254,000 mi,
replaced heater core
1995 Chevrolet S10 227,426 mi,
it has not been fixed yet but as soon as you poor in water or antifreeze, all of it just dumps out right in between the engine block and the transmission which leads me to believe it is the intake gasket or a blown out freeze plug.
Radiator core sprung a leak and fogged up the cab. I was able to limp it back home and spent two days to replace it.
1992 Chevrolet S10 63,600 mi,
replace heater core
1995 Chevrolet S10 100,000 mi,
It's a minor drip leak and tolerable, so I live with it. Detailed replacement video is on YouTube. Repair is too expensive and risky.
1995 Chevrolet S10 132,000 mi,
The dex-coolant cause radiator, heather & cooling system ( water pump replaced ). It was a big mess & cost to fix. Sometime in 2008 there was a lawsuit, but I was to late to make claim, 10/28/2008. Also, every 2 years I have to repair & replace parts for it to pass smog inspection ( a problem since it was new ), no one seems to know how to fix it. I am the original owner. The fuel pump has also been a problem. The airbag light has is also on we no fix. Otherwise the truck drives great and we love it. It is fast & pulls jets or boat easy.
2001 Chevrolet S10 89,500 mi,
heater core leak
1997 Chevrolet S10 147,386 mi,
how to connect to engine of motor
1997 Chevrolet S10 180,000 mi,
First off, I still haven't fixed the problem. The story is a warning. Started with a foggy passenger side window and only on the right. The thought of replacement was to replace the vehicle but before I was able to sell it, stepson used his car for "texting and missing a deer and then hitting a tree". Needs a car to get to work, you can use the truck 97 Chevy S-10 V-6. "Make sure you check the antifreeze cause it leaks", I warned him. He said there was no heat for a few days and then it overheated. Desperate, he added some window washer fluid to the radiator until he cud add some antifreeze. But it was already too late. During the overheating, the head gasket blew on top of the intake manifold. We bought a $45.00 bottle of sealer and it worked for 3 days before the head gasket blew at the cylinder because I now have white smoke coming from the exhaust.
1997 Chevrolet S10 130,000 mi,
Have not fixed yet. May try this weekend
1993 Chevrolet S10 152,000 mi,
keeps over after I had a new water pump and gaskets put on also had new heater core replaced new battery almost damn new have done everything why is it still over heating and losing pressure
1999 Chevrolet S10 97,000 mi,
Same as everyone else. Owned GM's for 30 years. Never again. Never.
1992 Chevrolet S10 13,200 mi,
Leeking coolant on right side inside of cab
2003 Chevrolet S10 140,000 mi,
Heater core began to fail causing the windshield to fog and the cab smell of antifreeze. Took to repair shop had heater core replaced.
1992 Chevrolet S10 190,000 mi,
The water heater system has a leak in it. I unhooked it and haven't got it fixed yet. Money is currently tight