Coolant issue

[ice91]

Last year I replaced the T-stat upper and lower hoses and the water pump in my 2002 grand prix. Less then a year later I was having issues with the heat, I checked the T-stat agian and it looked like there was orange silicone all over it almost like mud (but not slick). So this time i flushed the system using peak coolant flush and changed the T-stat but there is some type of reaction going on in my coolant system and idk why. I have pictures of the T-stat but I am not sure how to post them yet. Any ideas?

[TheOtherNick]

Thats what dex cool does when there is air in the system.

[FordMan77]

Time to flush it out and go green!

[ice91]

So after doing the flush and T-stat agian now I am having really strong coolant smells inside the car. Heater core is next right?

[FordMan77]

Are you getting a fog on the inside of your windshield near the defrost vents? If so then yes, heater core time. Just went through this on my 00 GT except mine decided to belch all its coolant out onto my floorboards.

Wasn't extremely hard to do, just time consuming with all the junk you have to remove.

Jay

[matt5112]

When you say flush, was the water that was coming out as clean as the water coming out of your tap?

[ice91]

Yeah i bought one of those flush kits tapped in to the heater core lines and ran it till I saw clear water (well almost completely clear). I then bought super flush liquid from peak and ran that through the system for a good 30 mins or more. Sucked out all the coolant and filled her back up with Dexcool. Ran the car with the cap off for a good 10 to 15 mins toped off and capped the system. Got some good heat for a day or so now heat is alright, but seems to have gotten colder and a strong smell of dex cool when I turn on the heat.

[matt5112]

I'd be inclined to believe fordman on this one.

[ice91]

It hasn't been cold enough for fog here yet, but when the heat is turned on it is one hell of a coolant smell. It's almost over powering its so bad. I have 131k on my 02 and it runs like a champ but now I am thinking time to do upper and lower intake gaskets and the core. What do you think?

[ice91]

So my head ach keeps on going. I just came back for an 80 mile ride and had heat the whole way with some coolant smell still. Anyone have any ideas of how I can check the heater core without taking it out?

[FordMan77]

When my hc started leaking I noticed a spot of fog on the inside of the windshield near the defrost vent and a small trail of Dex coming from the bottom of the heater box (the big black plastic thing that sits behind the console). I layed on the pass. side floorboard and with a flashlight I was able to spot it.

If your hc is leaking then beware. I had minimal warning on mine from the time I spotted the leak to when it completely let go. I noticed my temp was rising quick and my heat went cold. Stopped about a mile from the house and filled the rad back up and by the time I got into my driveway the temp was around 250 and climbing. I was effectively emptying my cooling system onto the floor the longer I drove. Can't imagine that heat being good for the rest of the motor.

And yes, at 131K if the LIM/UIM gaskets are original, then I would be replacing them with the aluminum ones, get some new end gaskets and some gray GM sealant for the corners and call it done. Also get new coolant elbows and a set of fuel injector o-rings. Whether you refill w/ Dex is up to you.

Don't forget to check out your UIM for issues around the EGR pipe. I replaced mine with a new one from ineedparts.com and it included the smaller diameter pipe for the LIM and it also has a metal ring embossed into the UIM where the pipe passes through creating a nice air gap.

[ice91]

Thank you all for your replies. I am just at a loss as to why i am not seeing any abnormal temps and how I can drive for 80 miles and have perfect heat, but still have that coolant smell inside the car. Any ideas? I just checked and looks like i can see RTV sealant from the lower intake so I am guessing that the gaskets have already been done. I am the second owner of this car and not sure if the prvious owner did it. Looks like I am going to hit the core and hope for the best this weekend.

[ice91]

Got the new core in and am now on fire inside the car. The old core was def leaking but not to the pass side it was leaking on the drivers side right near the gas. Boy was that a fun Job to do. Now that thats said and done has any one ever replaced there core on a 2002 gt? I had to dissconnect the switch that changes from the vents to the defrosters and while doing it I noticed a air sound coming from it. I know all the doors are vac driven and now noticed that the knob controling them is kinda loose when I change it from one to another.