I ignored my "low coolant" light a couple weeks ago because I had JUST refilled it about a month prior. Then I noticed that I was leaving huge puddles of fluid everytime I backed out of my parking stall and witnessed it dripping. The car overheated because of the large amount of coolant that I had lost, and the engine nearly seized. I added more coolant and took it to GM the next day. They had the nerve to tell me that NOTHING WAS WRONG. I'm pretty sure I didn't imagine everything that had happened the previous day, how dare you tell me that NOTHING IS WRONG. They did a pressure test and couldn't find a leak anywhere in the coolant system. Well, today I walked out and witnessed my good 'ol grand am leaking another pint of coolant. GM was too booked to take her today.. how convenient. Im amazed everytime that mechanics are just as clueless as I am when it comes to their own vehicles acting up!

My 1999 Pontiac Grand Am leaks anti-freeze sometimes and sometimes it doesn't. When it is above 85 degrees outside it pours out, but the thermostat gauge does not read that it is overheating. I have recently had the water pump replaced and a new thermostat and a new seal for the thermostat housing replaced. My neighbor told me that he believes the antifreeze is leaking out the overflow hose. I can't find where exactly it is leaking and did not see it coming out the overflow hose myself. I have to check and make sure the water level is ok about every 25-40 miles. On a hot day I have to stop and keep checking it and fill it up about every 10-15 miles. I'm worried it is going to crack my block. I haven't taken it to another mechanic because it only leaks extremely bad on hot days and each time I ask my neighbor to look at it after I have driven it for a while it is not leaking..????

Well I didn't do my home work before buying my grand am! Now I'm stuck with a car that leaks coolant from the day I bought it, always out of the over flow in the coolent tank. This past week the car started to steam. I was told that the water pump was shot so I replaced it. Now the damn car is over heating, the coolent light keeps coming on and its still pouring all the coolent out of the overflow tank! My machanic believes that the cooling fans behind the radiator are not coming on so advises me to change sensor that controls this problem.

Sounds about the same as others. Pontiac made a HUGE mistake when they built the 99-05 grand ams. Most gaskets are made of plastic. Yes, plastic! My car started out overheating. I checked all the usual suspects. As I was looking under the hood, I noticed water leaking from under the tstat housing. I then proceeded to disassemble to find the problem. It was easy to find. If you take the plenum, fuel rails, top intake and bottom intake off, you will see that the engine is V shaped. One gasket on one side and another on the other. Heres the problem: at the bottom of the V is a 2" space where no gasket goes. Its simply a bead of RTV. If your car overheats alot, that rtv will blow out and leak coolant. Im doing a complete upper end gasket change and using a higher temp rtv for that small area.

I hate my 99 Pontiac Grand AM it has been a peice of sh*t since I got it in 02 I have replaced the crapy plastic window peices that cost $40 a peice "dealership only part" the brakes go out every 3 months it wont take gas when its hot. The radio/cd player went out, water pump, thermostat, Temp sensor. EGR valve, the trunk leaks, alternator...twice. the power steering pressure line... thats $80 because it has "variable steering" what ever that means and the pump.....twice. weel bearings...3 times. window moters 3 of them waiting on the fourth one to go anytime now. the presure cap on the res. cross threaded and has to be pryed off with a screw driver. and countless other things im to pissed to remember!!!!!!! but now the damn intake manifold gasket decided to blow out of the blue and I have water in my oil I'm done with this peice of sh*t im going to push it off a cliff!!!!!!!!!!!!!!

i bought a 99 grand am everything was fine until it started over heating and i was ok fine i bought it used just anthers problem right? i figured may i just need to replace the water pump so i did, thats didn't work so the next day i had the thermostat replaced and the system burped and that worked for a couple days then the tensioner pulley melted and broke completely off the belt system so i put a brand new tensioner pulley on now im back to the same damn problem it's OVER HEATING AGAIN!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! and i can't figure out why if anyone can give me some info i would really like it.