I have an '01 Buick Regal GS with the supercharged 3.8. The car was running sluggish one Oct. morning back in 2005. I stepped into the throttle to try to clear it out. The motor started knocking and missing. My friend checked it out and discovered the intake had antifreeze sitting on it. Replaced the intake gaskets, fresh oil, filter, etc. Still making noise and missing. Front head taken off. Broken valve spring replaced. Still the same. Back head okay. Motor is now out. Heads, intake, oil pan off. Rod bearings look alright. Don't know where to go now. Have heard that the intake gaskets were a problematic thing with some of the sc 3.8's and that other people have had cars with similar problems. Any thoughts?

SOURCE: I have an '01 Buick Regal GS with the supercharged

Make sure the timing chain and gears are in good condition. This motor has sensors that tell the onboard computer about how it is running and the computer adjusts things like timing, gas air mixture and such. If there is a bad sensor, it will cause this motor to miss, run sluggish, even knock and generally run poor "if" running at all.
I suggest you go to your local parts store and buy a Hanes Auto Manual for this vehicle and bone up on what sensors are present and how this system functions. You will find that this manual will provide insight on most problems experienced with this vehicle. It will also provide you will valuable information you will need to properly put this engine back together correctly. Good luck.

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