Ok Gentlemen, I have another issue I need advice on. SO a few weeks ago I was driving my car with the heater (front defroster on) on full blast. After a while I noticed that sweet coolant smell, but i thought it was the truck in front of me so I rolled my windows down and aired out the car and that was the end of it. Yesterday morning I am on my way home from work and almost immediately the coolant smell starts (again heater on full blast) and when I get home there is smoke/steam in my car. i research it and figure out its a bad heater core. So i go today and run the car and get it warmed up with the heater on FULL BLAST for 20 minutes, yet nothing happens. No smell, no smoke.

wat do??

COuld it be that its just gunked up and stuff floating aroung and randomly plugging the core up? The heater does work as well, Very well at that. So that leads me to believe that it is not plugged up.I have checked and I see no water or condensation on the floor boards. I really dont want to rip the dash out for the heater core if I dont need to and it could just be flushed and fixed. But at the same time I dont want to flush it and something happen and the pressure break the core more (if it is broken) and have coolant everywhere.

Anyone have any advice besides the obvious of flush it and see what happens or take it out and inspect it?

thanks,
Matt

 

You'll typically smell the coolant when it's burning, it's a stronger scent. Anyway it's probably burning off/leaking near passenger side engine bay. The hose connection is right above the exhaust. It could be dripping and all the vapor is coming into the cabin in that area.

Has the coolant light come on at all? If it hasn't, it probably will soon.

 

unfortunately you'll have to run the risk of damaging the heater core more in an effort to find where the leak is coming from. you can rent a coolant pressure tester from kragen or auto zone, pump up the cooling system to about 15psi and inspect for leaks.

what you also have to realize in doing so is that if you let it go you may wind up on the side of the road with a tow bill and wind up having to replace parts/heater core anyways.

if you want a temporary solution because you have no money or time to fix it, you can bypass the heater core or put ground pepper in the radiator(a small pepper shaker full is plenty, i have used it in emergency situations on my old beater F250 with a 4 gallon capacity cooling system and worked like a charm), it will go to the leak and plug it up but will also clog some passages of the cooling system/heater core until you flush it out. the car will smell like cooking pepper instead of coolant though...

 

Everyone always assumes the dash has to come out to get to the heater core, but it's actually a lot easier than that. There is a little plastic cover under the driver-side dash that can be removed to expose the heater core and both the inlet and outlet pipes. There are 2 rubber hose connections that can leak, and cause coolant to vaporize on the hot core. When I replaced my heater core, I got some hazing on the windows initially due to a small amount of coolant that had dripped into the cavity the core slides into.

 

Prior to this I had some issues with the cooling system. The car had the wrong radiator cap and adapter to the water neck. So i got the correct one from mazdatrix. So once I got the correct one and the system held pressure, my water pump went out. So I replaced that with a new one, and now I am having this issue. lol

Since replacing the water pump I have not had a coolant light come on, But prior to repairs it would come on so It does work. I can park the car for as long as it takes to fix this car as it is my secondary vehicle and I also need to replace the throwout bearing anyways. I wouldnt LIKE to spend the money if I dont have to for a new core, but I will if it is necessary.

Karak thanks for the advice I will get a pressure tester tomorrow possibly. Would you think itd be alright if I got a used one from picknpull and cleaned it out and everything and put it in my car, or do you think it would be best to not and go straight for new? Also would s5 heater core fit an s4? There is an s5 n/a vert at my local picknpull that I am sure will be scrapped soon and I could get the core from it and use it.

Can anyone send me a link in the fsm where it shows which hoses go to the heater core? or possibly pics of them? I am having a hard time finding what I am looking for.

Thanks everyone,
MAtt