2001 Camry 100,000+ miles. Check Engine Light is on.

You could have a pin hole in your hose or in your radiator.

Now have a repair shop do the proper testing & resolve

Need system diagrams,scan tool & evap smoke machine

they have knocked a pipe off somewhere its very tight under the bonnet ,take iit back and they will check it for you

4cyl or V6?? Have your ignition coil checked and you vehicle scanned for the check engine light. If this is a 4cyl the coil is inside the distributor cap (possible oil leaking into the cap, very common on 4cyl camrys). If its a V6, have the Crank and cam sensors inspected. Hopefully this helps!!

wow thermostat >>>> shucks i believe its evep emissions code like faulty gas cap ....you can reset any computer the chck eng light will come on in 50 to 100 miles if not fixed....

Your check engine light usually means there is an issue with your emissions control system. The last time mine came on, I found that my gas cap wasn't on tight enough. I turned it on tightly and the light went off after 30 miles or so. Start there.
If you've tightened the cap and the light is still on after 30 miles, you may have a bad gas cap OR maybe you just got some bad gas at your last fill-up. Try a few gallons of high-test and drive it a while. If nothing changes, a new gas cap is probably the next cheapest option. Good luck.

My '06 Corolla's CHECK ENGINE light came on the other day and then went out after about a half hour. It was back on this morning and stayed on, and I noticed that the automatic transmission was shifting a bit more roughly than it ever had before. Took the car to a Toyota dealership immediately. The guy told me that Toyota has had an ongoing problem with the CHECK ENGINE light coming on due to a faulty CPU (car's computer "brain"). This has been affecting models from '05, '06, and '07 according to him. He said Toyota had extended the warranty for this particular part (i.e. the CPU) due to it being faulty. The warranty expires once you reach 80,000 miles, and my car has 87,000 miles on it (yes, I do drive that much for my job!). But the guy at the dealership was kind enough to put in a new CPU for free because I have been a good, loyal customer there. The CHECK ENGINE light is now off and it should stay that way.

Hi If you have not notice any changes in the engine performance is very posible that the oxigen sensor is defective, they last about 60,000 miles, if you have a utozone or chekers store near by they will diagnosis your car at no charge,C1....

are you fueling car with engine running? sounds like it is seeing an evap system leak. cannot fuel with it running. also check your gas cap

I had the same problem. I went to the kia dealer and they checked the code that caused the light to be on and found I had a leak in the gas cap. They replaced the gas cap and the problem went away. You night need to find out what made the check engine light go on in the first place.