How do you replace the cam sensor on 1990 Buick lesabre?

Answer 1

take out the 10mm bolt.

Most sensors do not go bad , but the magnet on the timing gear will deteriorate and the sensor can't read it. This would require the timing cover to come off and timing set to replace the magnet.

There is a trick to avoid taking the timing cover / timing set and just involves removing the bolt that holds the sensor in place and rotating the harmonic balancer (engine forward) until the spot where the missing cam magnet lines up with the opening. In my case I didn't see any sort of magnet left, just some plastic remnants. Clean it out well, then use jb-weld to secure the new magnet in place. You will have to modify the magnet by removing the brim portion (since you're not inserting it behind which is the factory approved method). You will understand why you will have to lean it out well, I had a few false starts until I got the last of the plastic remnants out, then I felt it fit in just fine. You have to allow time for the JB weld to set before putting everything back together. (You will have taken the water pump pulley off (not the entire water pump) and moved the antifreeze overflow tank out of the way to get room to work. I did this specifically on a 1990 Buick Lesabre and had no issues.

Detailed instructions (and useful images on the 'hack' here)

http://padgett.ws/cars/cammag.htm

- should note that GM/the mechanic I talked to, and many others will recommend doing it the standard way, and I in no way take responsibility for people using modified methods to repair their car. /CYA statement