I need help diagnosing problem with my Buick Regal 2001, 3.8 L engine. It bogs down anytime it goes into passing gear and will not accelerate until you let off the throttle. Fuel filter and spark plugs have been replaced. Otherwise, it seems to run fine. No engine check lights are on.

Welcome to AF, check fuel pressure under those conditions to start with.

Also it would be a good idea to check out our advisory notice at the Buick Tips & Maintenance forum about 2001-2002 Regal CAT convertor issues.

Click here (http://www.automotiveforums.com/vbulletin/showthread.php?t=681281)