Engine Coolant Question

[dowtrader]

This might be a silly question but I am doing it for the first time and don't know much about cars so i need some advise please. My coolant light comes on when i start the car. After driving it for 5 minutes it goes off. I am thinking to add some coolant. I know the plastic coolant holder on the driver side under the hood. I will add to that. Do i also have to open the radiator cap on the passenger side and add there as well. My car is 1998 Grand Prix GTP.

Thanks

[IndeedSS]

Add to the overflow bottle only. There is a line a few inches from the bottom,that you fill to. IF you over fill, when it gets hot, it will come out the over fill tube on the back side of the bottle. I overfilled once and for the longest time I though I had a leak. I parked on a slight hill one day and heard the dripping. Man I was happy that day.

[hotshot]

Make sure you check the coolant. If it is red it still has the factory dex-cool wich cannot be mixed with the yellow stuff. If you need to add you have to add dex-cool or a certian prestone that will say on the bottle that it is safe to mix with any other coolant. Otherwise it will gel up and or turn into a sand like slugde and that will be a problem.

[dowtrader]

Thanks a lot for your valuable advise. I looked at the coolant bottle but there are no marks anywhere indicating LOW or FULL or something that tells me the limit. Can i fill upto half bottle?

[IndeedSS]

The line is barely above where the hose from the radiator connects. I would only go 25% if you don't see the line. btw there are no words just a raised line the same color as the bottle, which makes it hard to see.

[JoshMcMadMac]

Make sure you check the coolant. If it is red it still has the factory dex-cool wich cannot be mixed with the yellow stuff. If you need to add you have to add dex-cool or a certian prestone that will say on the bottle that it is safe to mix with any other coolant. Otherwise it will gel up and or turn into a sand like slugde and that will be a problem.

Green stuff cannot be mixed; if it is yellow it is supposed to be safe to add to any coolant. I have only seen the stuff made by Prestone.

[dowtrader]

I checekd the radiator. It's filled upto top. I also filled enough coolant in the reservoir bottle but my lights still stays on. this is what happens. When i start car in the morning it stays on for 5-7 minutes and after that it goes off. Could this be because of bad sensor? Where is the coolant level sensor in 1998 Grand Prix? Is this something i need to replace right away? By the way temperature stays within acceptable limits.

[phat_ridegt]

if the light stays on and the radiator is full, change the coolant level sensor located on the passenger side of the radiator. very easy to do. pull headlight, use a screwdriver to remove metal clip, and pull it out. if your fast enough, you wont lose too much coolant.

[Zef_66]

[SyntheticShield]

Very nice Zef.

[Zef_66]

Very nice Zef.

Courtesy of Eric on clubgp...aka Houndi.

[Deezul_AwT]

Am I due for a round of part replacements as I'm about to hit 100K miles? I replaced my MAF sensor a week ago, and this morning my LOW COOLANT light came on. I replaced the UIM in April, so theoretically any coolant leak was fixed. My overfill tank was at about the house line, and I had some quick fill so I was able to fill it up. But I haven't seen a leak, and my oil didn't look gooey or that any coolant was in it.