Hey guys, I posted this question a few months back because I have been way to busy to follow up with the issue.

I have a 2003 Evo 8 with 28k miles and for some reason my heat does not work. I sometimes get luke warm heat but its pretty **** poor. Someone on the forums here said I had a bad heater core? Sometimes when I get back from driving a notice a small puddle of water in the morning on the left driver side of my car but its not directly undernear the car. Should I be really worried about this issue?

Thanks!

 

How is your coolant level?

My guess is the heater core itself is leaking. Taste the water on the ground; is it sweet? if so, its probably coolant.

 

Man, the evo that i'm looking at has the same issues. For some reason there is resistance when I try to turn it to the heat end as well. It's getting colder over here and GA and I don't want to freeze my **** off.

Having my mechanic look at it. I'll report back if he finds out what it is.

^LMAO at comment above

 

Even if the heater core is leaking, it should still heat your car. Probably your thermostat is stuck open

 

I also have an 03 evo and there is great resistance when i try to turn the knob to heat. There appears to be a technical service bulletin that Mitsu put out about the 03 model years having a weak gear linkage for the cold/hot knobs.

 

tsb for knobs

https://www.evolutionm.net/forums/mi...hard-turn.html

 

The heating knobs are a little difficult to turn but not that much. I don't think my heater core is leaking because I checked later today to see if I had any leaks and there were none. The coolant level is normal, but I have no idea what else it could be?!

Should go ahead and order a new core for 180 bucks? Or should I shovel out labor costs to properly diagnose the problem. Ahhh!

 

Flush the coolant system out. Mainly the lines in and out of the heater core. You probably have an obstruction. Good luck.

Aaron

 

Could it be a bad thermostat?

 

bad thermostat!!!

 

flush and change the coolant, and thermostat

 

https://www.evolutionm.net/forums/ev...n-problem.html

 

is your motor reaching its normal operating temp? if so its not the thermostat. a thermostat stuck open wont allow your car to reach its normal temp, it'll always stay cool

 

Start with the easy stuff that doesn't cost a lot of $$. Flush the system and see if that helps. If that don't work you could pull the t-stat out and test it or you could just pay the $$ for one. I haven't looked for an evo but I know they aren't that expensive.

 

Log the car and see what kind of coolant temps you see. You should get about 188°F when the car is fully heated up. If it's constantly less than that, get a new thermostat. If it's right there or higher, get a coolant flush done. It's cheap and might unclog whatever might be blocking your heater core. Also, feel both of the lines going into the core (engine compartment, they plug in through the firewall) and see if both feel hot.