coolant leak inside the vehicle

I noticed that there's a really bad stink of coolant when I'm on the freeway, and I just noticed that there's coolant leaking from under the dash on the passenger side. Where is this leak coming from, and how hard is it going to be to fix it myself? I've done some work under the dash, but not to this extent.

I noticed that there's a really bad stink of coolant when I'm on the freeway, and I just noticed that there's coolant leaking from under the dash on the passenger side. Where is this leak coming from, and how hard is it going to be to fix it myself? I've done some work under the dash, but not to this extent.

I had the same prblem with my 89 S-10 blazer. I had to replace the heater core under the dash. It is not a job for a rookie, you will have to start under the hood and disconnect the heater hoses and disassemble the dash to get the heater core out. I picked up a replacement core at Auto Zone for approx. $50. Good luck!

Just a note first, Check the connections on the engine side first just to make sure they are tight. Sometimes if you get a leak out front it may run inside. If you can rule that out then yes I would agree its the heater core. And yes it is a big job. figure about 8 hours if this is your first one.

Just a note first, Check the connections on the engine side first just to make sure they are tight. Sometimes if you get a leak out front it may run inside. If you can rule that out then yes I would agree its the heater core. And yes it is a big job. figure about 8 hours if this is your first one.

Right on! Yes check the heater hoses under the hood first. Most models have the connections right up next to the firewall and the opening into the cab is not sealed well or the rubber seal has rotted and fallen out (or in). Any leak in this area could blow into the opening and cause the smell and accumulate enough to run or drip into the cab.

The dash disassembly on my 89 S-10 was made a whole lot easier by having a full assortment of 1/4 and 3/8 inch sockets, including phillips head, and torq (star) head attachments, and about 5 different lengths of 1/4 and 3/8 extensions, as well as rachets and screwdriver handles. It is all a matter of unbolting and unscrewing and using a lot of care and patience, and not breaking any of the plastic pieces.

I noticed that there's a really bad stink of coolant when I'm on the freeway, and I just noticed that there's coolant leaking from under the dash on the passenger side. Where is this leak coming from, and how hard is it going to be to fix it myself? I've done some work under the dash, but not to this extent.

Your heater core is gone.

Check the hose connection at the heater hose and if they are dry, replace the core.

Leaking engine coolant cannot run in from the engine compartment.

It is definitely the core.

Yup, the heater core is gone. Thanks for all the info, but here's another question. If I decide I don't need my heater, can I bypass the heater core, by using the hoses in the engine compartment? If it's possible, what will this do to the engine? Thanks again!

Yup, the heater core is gone. Thanks for all the info, but here's another question. If I decide I don't need my heater, can I bypass the heater core, by using the hoses in the engine compartment? If it's possible, what will this do to the engine? Thanks again!

It's possible to bypass the heater core. All you need do is disconnect the heater hoses where they enter the firewall by the AC unit and join them together with a 1/2" coupling.

Back in the 60s muscle car era, Chevy offered a "heater core delete" option on a select few models (Corvettes and Chevelles,only on the left coast). Of course, there were no "computers" with temperature sensors back then, but your fuel injection temp sensor doesn't run off your heater core either.

Try by-passing it until you need it. It'll only cost you maybe 15 minutes,two small clamps, and a small chunk of copper tubing (any hardware store has these couplings for about $0.25. (Be sure to measure the inside I.D. of the hoses for the proper size coupling)
Good Luck,
Mike

Yes, you can easily by just pulling the hoses out from where they enter the cab and splice them together.

Won't hurt a thing.