Started up the car yesterday and everything was good. Took it on the Highway for about 5 min. Opened up the car a lil bit, when I got off and stopped at the light the car sounded and felt like crap. Rough Idle, Slow Acceleration, Sounds like I got a V6 under the hood.

Has this happened to anyone? Need some input if you can.

Thanx.

MOD: Intake, 3" Downpipe and free flow cat, PFC, Ported Motor.

 

How much vacuum is the engine pulling and at what idle rpm? Have you checked to see if your map sensor vac line has come loose?

 

The engine is idling at 850-900. The Vac is at about -300. I will be with the car tomorrow and give you better specs on it.

 

compression test

 

Like David mentioned, check the MAP sensor...