This is the second time that this has happened and I wonder if it's normal. I get a cel when I run my car hard, I went to Tahoe this week and so naturally on the mountain roads I was driven pretty agressive but never went above 5200 rpm and red line is like 6k and I got the light that says engine coolant temp was too hot. I got it before when I first got the car and now it did it again. Does this happen to all 96's ordoI need to investigate?

 

Anytime you get a CEL you need to investigate. First off, are you low on coolant or is the level OK? Check the overflow tank and see if your level is right. If not, top it off. That alone could account for the problem. You may have a thermostat problem as well - you could pull it and put it in water with a thermometer and see if it opens/closes at the right temperatures, or you could just put a new one in. Make sure your coolant hoses are all in good shape and you're not showing signs of age with them (cracking, etc) - replace any that look worn.

That's a start anyhow.

 

I had the resavior topped off and there are no leaks there's something else going on here I think. I have a new Engine Coolant Temperature Switch (ECT) I think I should change that and the termostat and flush the system... I just bought this car a month ago it wouldn't hurt to make sure there's no issues with it. How many gallons does the radiator hold on a 96 a4 2.8l 12v?

 

Find out if your cooling fan is working too - that helps a lot and if it isn't coming on, you could start overheating. The fan switch may have died, or the fan clutch could've given out, so either of them would be worth looking into as well. Off the top of my head, I'm not sure how much capacity the radiator has.