Hi got a 2000 bonni ssei car runs great cold soon as it gets hot starts to miss and sputter can someone please help.

Check your coils. That'* the first place I look with a hot miss.

Can you isolate the cylinder in question? If so, a cracked plug, coils and even wires can cause issues once they heat up.

One easy way I like to look for misses is wait until dusk, start the car and mist the motor with water. A cracked coil or arching wire will light up and show you where the issue is.

whats the best way to check them?

thank you i will try that

You can pull the plugs and inspect them. You can scan the engine for codes. Your looking for P030X codes, the number for the X is the cylinder. If it'* a 300 that'* a random misfire. Here'* how you test the coil. https://www.gmforum.com/trouble-shooting-test-procedures-141/testing-coils-spark-plug-wires-278818/ Test them cold, write down the numbers. Then heat the engine up real good and test again.

And while testing the coils look for any cracks. The crack would make a nice spark at night with a misting.

Did I mention how much I like that test.