Why does my car rev it's self to 3000RPM in Park & Neutral?

Question

2001 Hyundai Accent 1.6L, New wires, plugs, fuel system flushed by shop with BG products line. New Fuel filter. I changed my air filter, then the problem became, I have rechecked my work, making sure box does not have an air leak....

The car will rev it's self up to 3000RPM in Park or 'N', back to normal when in drive. Car feel like it's jumping when driving sometimes... very intermittent....

Answer 1

check you're intake hose to air filter

make sure it put in all the way

Answer 2

You have a vacuum leak.  Cracked, broken or disconnected vacuum line somewhere.  Probably knocked it off when doing all that other work.  Happy hunting.

Answer 3

iacv, tps or large vaccum leak

Answer 4

since the problem appeared after having the fuel system flushed i would return to the shop and have them sort it out..

Answer 5

MAP sensor or MAF sensor? Just a guess.