Hello I have a 2006 bucik Lucerne and the engine stars but when I put in reverse or drive it doesn't move .can u explain to me why this has happened

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2006 Buick Lucerne Owner Manual M - Dealer E Process

dealereprocess.org https://cdn.dealereprocess.org > servicemanuals
2006 Buick Lucerne Owner Manual M ... Keep this manual in the vehicle, so it will be there if ... A French language copy of this manual can be obtained.
416 pages

2006 Buick Lucerne - Owner's Manual - 416 Pages - PDF

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2006 Buick Lucerne - Owner's Manual. Posted on 10 Apr, 2020. Model: 2006 Buick Lucerne Pages: 416. File size: 3 MB. Download from Buick.com. Online Viewer.

You are not alone!

https://buickforums.com/forums/threads/06-buick-lucerne-cxs-transmission-problem.61077/

https://www.google.com/search?q=2006+Buick+Lucerne+in+reverse+but+it+goes+forward

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try to remove the positive cable from the battery and wait for 5 minutes then install back the positive cable. start the engine and try to engages the gears again

first take hose off, or drain from drain plug. antifreeze is what you are draining. Then get a 15 mm rachett and socket and pry tension pully back so you can remove belt. unbolt water pump and take off. Once off clean engine block with razor blade,or something to get old gasket off. put a thin layer of rtv blue permatex on new water pump. Now put new gasket on new water pump on top of the permatex . let dry and set up, this will keep the gasket from moving around when putting back on. follow the process backwards and should b 30 min job . GOOD LUCK YOU CAN DO THIS FOR SURE. ONE OF THE EASIER ONES.........................

Hello-
According to Dayco, this is it. Give a quick holler if this doesn't make sense, sometimes they get it wrong. Engine code is always nice to make sure.

Fig. Accessory drive belt routing -3.6L engine .


Fig. Accessory drive belt routing -3.8L engine

Do an upper intake clean that will clean the throttle body and the Idle Air Control valve. Also clean the mass air flow sensor

If you mean the shifter is getting hard to move, its probably the shift linkage sticking, try a couple squirts of pblaster or other penetrating oil. If the motion of the vehicle is getting hard to drive in reverse and drive the torque converter may be the issue.

Has Coke or anything that goes sticky been spit around gear shift? I have had this before & had to pull console apart & clean with spray & wipe.

Cv axles normally click repetedly when moving ,doesn't sound like an axle,more like a motor mount or brake calpier .If you put your foot on the brake with the hood open ,put the truck in reverse and put a load on it and then in drive and load it you will be able to see the engine rock excessivly if a mount is bad.

I had the same problem on my 2006 Lucerne and it was the engine mount located on the front of the vehicle behind the radiator.