I looked at the engine compartment, it looks like no demage anywhere to the engine but when the car is running I hear a hissing noise (like some air leak) on the right side of the engine (i can not see anything there the car does not want to run
( BEFORE IT HAD AN ACCIDENT AND I WAS TRYING WITHOUT RAD JUST COOLING PIPES CONNECTED TOGETHER)
the car has about 12000milesdoes not want to run smooth and when pressing the accelerator it back fires

please help