Having problems with your 2001 Buick LeSabre ?
1994 Buick Lesabre Run very smooth when idling After warming up, while drive Car shudders after rpms drop when car shifts into overdrive
My guess is, the mixture is lean. If the oxygen sensor is old, the computer mixes in lots of air. Too much air, a heavy load, a warm engine, and you get missing strokes. At any rate, an oxygen sensor ought to be replaced on general principle after 50K miles. From a parts store, it is about $60. But you can find one online for about $25. It is real easy to replace. You see the oxygen sensor on the exhaust pipe just to the rear of the engine. It looks just like a spark plug with a wire attached. You need a 7/8 inch wrench or metric equivalent or preferably one of those short claws that are like a socket except they grasp from the side and turn with a 3/8 inch socket drive. It will be quite hot unless you let the car sit awhile before attempting to remove it. Since it is in a hot place, use anti-seizing grease when you replace it or you won't get it off next time. Also, bad spark plugs could be causing your problem. But change the oxygen sensor if it hasn't already been done recently.
Repair Help & Product Troubleshooting for 2001 Buick LeSabre
Tips for a great answer:- Provide details, support with references or personal experience .
- If you need clarification, ask it in the comment box .
- It's 100% free, no registration required.