miss and backfire
Hello, I have a supercharged 3.8 it runs fine going down the road. Half throttle is responsive but at wide open throttle the car will miss and backfire and will even die if you don't let off in time. I just bought the vehicle a few weeks ago and have no experience with this motor. What could cause this? Sometimes it will idle up and down while parked (not a/c drag) , don't know know if the 2 issues are related, maybe a vacuum leak? ( not audible), as in I can't hear any vaccum lines sucking. Otherwise car runs great starts right up, just idles funny sometimes, and is not responsive at Wot. Any feedback would be great I'm a carbureted small block kind of guy, I don't know much about the sideways motors.