Service engine soon light blinking

Why would my service engine soon light blink for 3 to 5 seconds the remain on, it had no noticable loss of power or anything else everything seems to be fine???

Blinking means that a misfire is being detected and you are doing damage to your cats. You should get this diagnosed/fixed ASAP.

i understand that bliking means misfire but why would it stop blinking with no power loss

The “check engine light” is NOT an engine performance light. It is an emissions systems light. A problem in the emissions systems MIGHT affect engine performance, or, it might not. Depends upon the defect.
An emissions system needs repair, on your car. Get the emissions systems scanned, and bring the codes here (in raw form, such as P0410) for advice.

Engine light on = get looked at asap. Flashing engine light = engine damage could be occurring, fix NOW.

What does the owner’s manual say about it?

i understand that bliking means misfire

I don’t know what year car you have but I would be surprised if it had light that just indicated a misfire.

On most modern cars a CEL (Check Engine Light) is really an indicator to read the codes that it stored in the car’s computer and the code will tell you way the light came on. Next step is to determine what caused the error code. Often the code may say something like XYZ is too high. Some people go out and just replace XYZ only to find it does not fixe the problem because they did not look to see why XYZ was too high.

Have the codes read and then bring the results (the real result codes in the format [P1234]) and let us go from there. Many autopart stores will read the codes for free.

BTW it would help if you told us want make model and year along with the total mileage.

Check your owner’s manual. Lots of cars now, mine included, have a service engine soon light that blinks and then stays on when scheduled maintenance is due.