[mellowyellowzx3]

not to sure if anyone can help me out but my car seems to be acting out on its own, and have no idea what would cause my engine rpms to rise drastically on its own, for example i was on the highway driving home and came up on some traffic so i pushed the clutch in after breaking to downshift and as soon as i push the clutch in the motor revs up on its own without my foot being anywhere near the gas pedal, my only solution is dump the clutch and let the mechanical drag bring the rpms down closer to idle in gear or just shift very fast before it revs to redline. so my question really is what might cause this and what can i do to fix it, thanks!