My daughter's 97 Civic had its engine replaced recently. Today, as the car
went over bumps she saw a light blinking. She thinks it's the check engine
light.



At the same time, the tachometer would jump 500 or more RPMs, but she didn't
notice the engine increasing in acceleration. I drove the car myself and, as
I saw the tachometer increase by 500 to 1000 RPMs, I heard a noise twice.
Not big nor long, but as if something was grinding against something. I
didn't notice the engine increase in RPMs either.



Any idea what this may be?



Than you



Tony