I clean out my intake manifold 4 days ago. After cleaning it, I drove around. The car was running fine. Until I got to a red light. The car reved up to 1500 RPMS. And it woundn't stop. And if you give a little gas while it is reving high like that it starts to bog. But if you give a lot of gas it revs ok. The only way it went away if I turned off the car and started it back up. But once I stop somewhere it would idle again at 1500 RPMS. My car was running perfect before I clean out the manifold. I changed my spark plugs yesterday , thinking that was the problem and I still have the idle problem. Has this happened to anyone?

 

have you adjust the idle?...it could be possible after you clean the IM the build up is gone...so you need to re-idle the car down?...

 

There's an idle adjusting screw on the top of the throttle body. You'll see it, it's a flat head screw, facing the inlet of the throttle body. Try adjusting that and see if it helps.