Popo54

I got a 2000 3.8 automatic with 116k on it. Lately my temperature gauge fluctuates from normal to almost overheating. Thankfully I make it to my destination before it overheats. I've read articles about the issues but thought i'd ask you all.

symptoms:

1- temp gauge goes from normal to hot on a 20 minute drive. sometimes while i'm sitting at a light it goes back to normal. clueless. I got home one time and I did see a little dripping maybe from getting too hot at the radiator cap.

2- my heater in my car goes from hot and then to cold while i'm driving. I ask this because I read that there is coolant going through the heater core that produces the hot air. please correct me if i'm wong. maybe my water pump??

??? I have read that it could be several things (rad cap, thermostat, water pump, radiator) but i need to know where to start. Is there a way to check each one of these myself before dropping a bunch of money at a shop.

thanks in advance for the replies. this is my daily driver so I need to fix it.

Matt's 95 Stang

I had a similar problem a few months ago and it turned out I had gotten a air bubble in the cooling system some how. The best way to check is to run the car about 5 min to get it ALITTLE warm. Pop the hood, open the rad cap and turn the car back on. If you see bubble come up from the radiator then you have a air bubble. While the car is still running put more coolent into the radiator till its full, or alittle over flowing. Put the cap back on and turn the car off.
I would try this first, if it doesnt work then I would check the thermostat as they do die after a while. You can check this out too before going and buying another one. If you take the thermo out, take it in the house, put it in a pot filled with water on the stove and heat the water up. If the thermo opens/closes then its not the thermo.

Matthew

Popo54

hey i really apreciate it..so just to clarify...turn it on for a few to warm it up...turn it off ?...remove the cap and turn back on or just leave it running the whole time....sorry just wanna get the sequence right....my bad....just new to the mustang world and still learning.

Matt's 95 Stang

Yes, turn the car on for 5 min or so. Come home, pop hood, open cap, turn car on and watch for bubbles (or air pockets) to come up, put coolent into rad with car is on and make sure you are full of coolent. Its ok if you put to much as you have a coolent overflow tank. Put cap on (while car is running) after the rad is full and you dont see anymore bubbles come up.

Matthew

NeoTokyo

Yeah, just sound like you have to burp it.

Now its a little different too than what Matt is saying because he has a 95'

For your 00' there is a black metal tube infront of the intake with a little screwed in cap on top. Undo the cap and fill that till it overflows.

You can do this with the rad cap off to top the radiator, you will notice that fluid overflows through the radiator fill when you fill the burp tube. Once that happens then recap the rad and continue to fill the burp tube.

Do this while the engine is cool and running.

It wouldnt hurt to repeat this again after a week or so of driving.

Matt's 95 Stang

oh yeah you guys and your stupid "New Edges" think your all better and us SN95s

Matthew

Popo54

Alright. I will try this and update. Hopefully this works.

petrock

I wouldn't recommend this. There is a lot of room for 'user error' and getting the motor too hot. Removing the cap when the engine is hot will result in the EXTREMELY HOT fluid spewing out very fast and causing some serious damage to the engine (melting plastic stuff) as well as your body (2nd degree burns).
If you have no other choice but to open the cap while the engine is warm/hot, don't unscrew it all the way. The radiator cap is a two stage cap. The first stage relieves pressure, and the second stage (requiring you to push down on the cap) disconnects the cap. After putting on a long sleeve sweat shirt and gloves, wrap a thick cloth/towel around the cap and rotate the cap slowly to the first stop. Step back and wait for the pressure to bleed off. When it stops hissing, it should be 'safe' to press down on the cap and rotate it until free. Be careful though, the fluid and the cap will still be HOT!!!

The procedure I use on my girly's '98 mustang is to wait till the radiator is cold to the touch. Remove the radiator cap and fill it with 50/50 mix of coolant/water. Press a plastic large funnel in the filler neck so it seals around the inside diameter of the filler neck. In they next step, the fluid will bubble up and this will help prevent it overflowing onto your motor. Then start the engine, with the heater on high and let it idle. The coolant fluid will bubble up and down a little as it lets the air out. If it drops to the point where you can't see it through the whole in the funnel, add more coolant till you can see it through the whole. Don't fill it to the top of the filler neck. Let the engine idle like this till the temp gauge is in the normal range. Then shut off the motor and let it cool. When its cool, top off the radiator and the plastic overflow reservoir. Thats about it… After a couple decent length drives, check the level in the reservoir and top it off if need be.

Good luck...

Popo54

!!!!!! i did it. fixed the problem...no overheat and hot heater air...thanks greatly for the help guys.

MustangSally94

My car is doing something similar but the heater is still hot... and i filled the radiator and added some to the over flow reservoir last night and this morning it was empty not sure if thats normal. the bottom right hose coming out of the radiator feels like it might be leaking... should I try bleeding my cooling system first or see if I need to replace a hose or the radiator its self?