How can I disconnect check engine light?

Im tired of fishing for the computer code problem with my friends car. I have changed 3 o2 sensors and a TPS because thats what the code reader said was the problem. It was a waist of money, it still says check engine and the car still runs like brand new.
I just want to turn the light off.-thanks

It is on for a reason, you need to try and find the reason. Replacing parts is the wrong way to go about it. Do you have a service manual? If not get on and try the diaognastic flow charts.

Im tired of fishing for the computer code problem with my friends car. I have changed 3 o2 sensors and a TPS because thats what the code reader said was the problem. It was a waist of money, it still says check engine and the car still runs like brand new.
I just want to turn the light off.-thanks
like whteg said its on for a reason
You need to get the diagnostic codes to find out whats wrong I have had good luck using a jumper lead and just counting the flashes of the check engine light
What year is it ? OBD1 orOBD2
onjce you know what codes the On Board Diagnostics say then start trying to replace things

Thats why I started changing things because my light was on. What I was saying was everytime I change something there is a code for something else but the car never gave me a problem.

Have you tried to reset the ECU?