Overheating issue
 

So i was coming home from work the other day, the day that started this heat wave and my car started overheating. after pulling over numerous times to let it cool i got it home. So today i flushed all the coolant out and switched from dexcool over to the good ol green stuff. also changed the thermostat. car ran good after, but took it down route 9 and it slowly went up in temperature until it was way up there, about 230, 240. What could be causing it to overheat? It does start to bog and lose power so im going to check the cat to see if its clogged but else could be wrong with it? im still on a stock tune with an lt4 hotcam, could that have anything to do with it?

fans turning on?

yeah check the fans. if you have a/c that works, you could turn that on to check their operation. shouldn't that car not be dexcool? they started late 95 for the 96 models i thought. and i believe that was v6's first.

Engine was rebuilt so i assumed he switched over to dexcool. No A/C in the car, but the fans are hotwired to stay on all the time. Coolant looks like its circulating fine when you have the radiator cap off, so i don't know if it's the waterpump. after i flushed it you could hear the air bubbles and the temperature would shoot up so i burped it and got them out. it slowly goes up, but i thought it would stop, but just kept going and going.

you used the air bleeders? so the fans do come on?

edit: even though he rebuilt the motor, he shouldn't change the antifreeze type. the gaskets are different material.

that used to happen in my camaro, and it turned out one of the electric fans was busted. Although i know when i turn them on they usually go on, i still checked them, one of them wasnt working and one of the wires was lose. a little soldering later and the fan was arrite and it cooled down alot.

my camaro still runs up to 220-230 everytime i drive it, its wierd because i have a huge radiator with 2 electric fans on both sides, not sure if thats the usual temperature but it does get hot in there. so im in the same boat with you bud

lincoln Mark 8 fans are amazing.....they are a bit big, but the flow something like 4500cfm ( single fan / 2 speeds)....you can usually get them for about $75 on ebay and the like. The same fans came on a couple other ford/mercury vehicles, I believe also. If you guys can make them fit, they are the way to go.

my car used to overheat and i figured out it was the fan but the past few days in this heat its been getting to like 200-220 degrees but been running fine besides a little "miss" here and there...like u hit the gas and it has a delay before it goes..

i'm sure i will have the know-it-alls tell me how wrong i am:

there was no reason to swap out dexcool unless it was time for a coolant flush anyway...dexcool actually cools better than green antifreeze, so like i said unless its life was depleated I highly doubt that was where your problem was.

Like everyone has said, make sure your fans are turning on, that is key. I hope you still have A/C in the vehicle, and with that said if you are running it with it being a million degrees out, that condenser will get super hot super fast...the fans need to be working or the radiator will just have super hot condenser air coming over it = not good. If no a/c, the fans still need to be working to cool the radiator down with it this hot outside. Also, make sure all factory designed equipment for directing airflow (i believe on 4th gens there is still an air dam) are intact.

Let us know where you end up from here. I would think to check thermostat operation, and make sure the water pump isnt weeping.

240!!!! :shock: Dude my car blew the headgasket at 245! Be carefull! If not your gonna be having people over to change your headgaskets soon too, hope not tho.
Good luck

Like i said in all my previous posts, the fans are constantly on.. from the second the key is turned on before you even start the car, the fans constantly run. thermostat was just replaced, it could very well be the waterpump but it appeared to be working correctly. I wasn't sure that my car came with an airdamn seeing as this is my first 4th gen and it never had one on there. So a 94 Formula came with an airdam? if so i'll pick one and that should make it run a whole cooler, no?

You do have the correct LT1 themostat, right? For the right flow direction? Many parts houses will give you the wrong one.

does it cool ok sitting still/just get hot on the road?

It gets hotter when driving, then again i've never really let it sit there that long. and the thermostat is correct, it's from my family's napa ;)

air dam is very important - 3rd & 4th gens are bottom breathers. IMO you shoud have the fans wired correctly, but deal with that after the overheat issue is resolved.

My 82 ran very hot with oe rad, clutch fan. I put big a 3 core rad & 160* stat in it, better but still hot. Single electric fan setup out of an 85 with switch to come on ~180*. Better, but still hot on the highway. The OE air dam was broken so I added the biggest new GM one I could get (gm appeared to make them bigger in later years), problem solved. Car would never break 185* on the hottest days, idling for 30 minutes or 85mph on the highway. It's all a system and the heat will find the soft spot in the system.

madness, you should shake those pusher fans they probably impede airflow more then they help, esp at highway speeds.

Well i wired up the fans to be constant cause thats what i thought it was. i replaced the relays but i couldn't figure out why the fans wouldnt turn on. but im going to buy an airdam now and ill see how it runs after that. Fact is i never realized 4th gens had air dams, my fault, my first 4th gen so i didnt realize it.. thanks for the help guys

Wow, so i went down to B&B auto wreckers, where they actually let me go back and take off a v6 firebird what i wanted and i bought an airdam. $25.. wasn't so bad.. put it on drove it around didnt go much over the first quarter dash.. that 180? 185? so i'm happy about that.. never thought that that one piece of plastic could cause so much problems.. thanks again guys

woot! next fall we fix your fans!

yessir now i need me an exhaust

Now I really need to get me an airdam and shroud!! Wheres B&B?

btw the other reason to have dexcool is because you have an iron block with Aluminum heads :) has something to do with the different metals. and if you didnt fully drain and flush the dexcool and just put the green stuff in, plan on having more cooling issues when it turns to mud.

me and my dad sat there for hours and hours just filling with water and draining and repeating im pretty sure i got it all out.. but we'll see.

i could have sworn they use different gasket materials with dexcool. that may cause a problem. find out eventually.