PontiacBonnevilleClub.com

So, I'm not sure if this is a big issue, but I digress. The engine thermometer is already a tad above 200 degrees as is (getting stuck in Cleveland traffic for an Indians game is never fun). I have 2 summer classes (46 mile drive there and back), and my engine seems to be heating up a bit more while waiting at the lights in town. But, when I start moving again, the cooling system seems to pick up the slack and gets the engine temperature back to optimal. I don't know if there is a way to fix this "issue", but I wish to have this car running for at least 2 more years. Maybe a coolant flush is in order? I'm not sure. This has been happening for about 3 weeks so far.

I would check the level and strength of coolant and also check the hose from rad to overflow bottle - the clamp on mine rusted and broke causing a leak.

I'll give that a look. Could another issue be that the giant cooling fans aren't working properly? I was told that could be one.

sounds all normal to me. T-stat is 195* and if there is not air flow in heavy traffic it will go slightly above to like 210-220. I would also agree to check the fluid level when cold in the Radiator and the overflow, if thats good i wouldn't worry about it unless the needle gets near the top of the gauge (then you have a problem) or is boiling (too much water and not enough coolant mix).

S

Cooling fans are set at 212 and 225 or something like that. These cars run pretty toasty from the factory. Give her a coolant flush and a new thermostat. It's all pretty cheap and good preventative maintenance.

Sounds like a plan! I'll see if I can get that coolant flush sooner than later. I've had this car for nearly 4 years now and I had no idea that the 3800 could get that warm without any issues. Thanks!

Most modern engines run that hot for emissions purposes.

All 3800's used a 195 T-Stat and had a high speed fan turn on of 227F, low speed was 210-212F..

The older Bonneville 88-99 had better cooling systems tho..

The 00-05 Bonneville had a skinny radiator and no option for HD cooling.. My 03 would spike to 225 on the highway climbing the mountains.. I never cared for that.. My other 3800 powered cars would never even hit 200F on the same stretches but the difference was that they both had HD cooling..

On the 03 I had to replace the radiator and was able to use a thicker core.. Now it does not get that hot with the same drive.. Not sure why GM never offered HD cooling on the 00-05..

Get rid of the coolant. Run distilled water and 2 bottles of water wetter. If you can find one, get a 160 tstat drill it and get a tune for early fan turn on. Kill the heat, the kill the KR.