How to repair when the check engine light comes on.

Yes you do. Some cars like my Lexus will self check and sometimes turn the light off once a certain number of positive results have been recorded.

Normally, when a CEL comes on, you cancel it and if it comes back, you fix the issue based on the DTC Code. Then you clear the code and cross your fingers.

You need to get the computer trouble codes scanned
Check engine light on Part Ricks Free Auto Repair Advice

No, the problem lies elsewhere.
Get a diagnostic check done to identify the fault

My Engine Check Light Is Illuminated

Clearing the Check Engine light does not repair anything - it only turns off the light and clears the error codes. The problem(s) that caused the light to occur are still going to be present and the light will probably come back on, anytime from a few minutes to a few days depending on the problem(s). What you NEED to do is to extract the error codes that come with the light and take the corrective action(s) to repair the deficiencies. That will probably make the vehicle able to pass smog checks. Of course, now that you've cleared the Check Engine light, you've also erased the error codes, so you will need to wait for it to return to get the data you need for repairs.

The smog check requires a visual inspection of your check engine light. It has to come on for a bulb check at startup to make sure it's working. But, the light must go out after starting the engine(it cannot stay on after the engine starts during a smog check). If the check engine light fails either of these two tests, the vehicle will fail the smog check inspection.
You need to have the cause of your inoperative check engine light diagnosed and repaired.

Once the problem that caused the engine light to come on is repaired the light will go off. Resetting it without a repair will not keep it off.

You should not drive a car if the check engine light comes on and you do not know what the problem is. In some cases the check engine light means a serious problem and I know could cost a lot of money to repair. Mine came on and cost $800 dollars to repair as I tried to drive it.

Your Jeep ecu is in need of repair. Your jeep is having a common problem known as the "Delayed check engine light" starting problem. Next time you try starting the jeep and it the fuel pump won't prime, look at the dash.....the check engine light is not on and the fuel pump will not come on until the check engine light eventually come on, on the dash. Have it repaired and it will eliminate the delayed check engine light start problem.

If the timing belt keeps breaking and bending valves, the timing belt and cylinder head repair is not being done correctly. It's as simple as that. Are you changing the tensioner and idler pullies when replacing the belt? Is it timed correctly? Was the timing belt tension adjusted properly? Were the cam journals checked for damage? If not, you are asking for another belt failure.

If you want to know why the check engine light is coming on, you will have to ask your engine computer. Every time the light comes on it is storing a fault code to tell you why. You must scan your engine control module to retrieve the fault code(s) so you can get it properly diagnosed and repaired.

Unplug the negative battery for five minutes; this will reset the ECU; if the check engine light ON again, scanning for knowed what fault codes is there.

Hope this help (remember rated and comment this).