i have a 1995 z28 its auto and i am having a problem whenever i sit at a fast food place or in a parking lot my car gets pretty warm and sometimes when my high fans kick on the ses light comes on then it goes away sometimes quickly sometimes 5 minutes later and with this problem after it gets warm in a parking lot it wont cool down to 180 it just stays up above 200 probally higher and it wont come down after im back to normal driving. so my question is if i get the pcm tuned to set the fans at a lower temp would that get rid of the ses light coming during high fan running and prevent the car from getting so hot and staying hot also sometimes it dosent seem like the high fan stays on very long or kicks in im lost also i have a 160 thermostat too i could put in

 

My 93 would do that all the time, its recommended to check and see what causes this but ive heard and seen this happen plenty of times. I just did what your thinking about doing got a 160 thermo and tune, called it a day. Make sure you have no air in your coolant its bled properly if youve done anything in the past that has to do with your radiator or coolant. Im sure people here would have a much better suggestion GL either way.

 

I had that problem and it ended up being my water pump. Replaced it and everything is good now. I could barely tell it was leaking but could see a couple lines where it had run down the block. I would also flush your cooling system if you haven't in a while and see what you get.

 

are you sure the fans kicks on then the ses light because if om not mistaken when the ses light comes on the fans should kick on with it. Maybe try getting the car scanned for codes