PontiacBonnevilleClub.com

Hello, and thanks for reading!

I recently acquired a 1989 Bonneville LE. My little brother had grabbed a handful of change from the change tray (ashtray), and dropped a penny in the cigarette lighter. The fuse failed to blow. This melted a lot of wiring under the dashboard, and my father was going to trash the car except I removed the entire dashboard, spliced in about 100 feet of new wire, then reassembled the entire dash again.

Now the car runs terrific (and all the lights and such work as well), except for an intermittent code 41 and 44. I have read on this forum that this could be due to a faulty cam sensor so I purchased a new one and installed it. Managed to do it quickly with a gear wrench, but this didn't fix my problem.

I have also read here, and in the Haynes manual, that the magnets are prone to failure. Due to the clearance between the block and the chassis there is no way I can really get a good look through the camshaft sensor hole to even see if the magnet is in place. I had an idea as to how to go about this, but I wanted your feedback before I started.

My thoughts were:

-Remove the front passenger quarter panel
-Drill a hole through the under body (to later be patched)
-Rotate the engine until I see the magnet (or a hole) [PROBLEM 1]
-Remove the magnet [PROBLEM 2]
-Epoxy a new magnet in place [PROBLEM 3]
-Patch and reassemble

Problem 1:
I don't know what the magnet looks like. I read it comes in a plastic housing. Any particular color? How large is the magnet relative to the size of the sensor? I figure the sensor makes a hole between the size of a quarter and a dollar coin, so I'm guessing the magnet is smaller than that, but roughly how big? Like a dime?

Problem 2:
I have also read that the magnet may be like putty if it even happens to be in the hole at all. How well seated is the old magnet? Would I need to knock it out with a punch or a drill, or could I just use a stiff pick?

Problem 3:
Is there any particular size or strength that the magnet needs to be? Obviously it needs to fit in the hole, but could I use just any magnet? If a specific magnet is required, where could I purchase it?

Also, is the positioning of the magnet essential, and how much clearance is there between the magnet and the camshaft? Could I just take the sensor out, swab the area, and epoxy a new, thin magnet in place anywhere, or does it need to go in exactly where the old one was?


While this is (can be) a nice car, I don't have the location or resources to partially pull the engine like I probably should to do all the work that it probably needs done on it. I'm trying to get this job done with the minimal amount of tools and time required.

One more question and then I'll quit. My father kept fuel and mileage logs for about 6 months and said that the best the car ever got was about 18 MPG. He also told me (after I did the dash work) that the check engine light has been coming and going since he's owned the car. Is this mileage normal, or can I expect to do better when I get this issue resolved? Please tell me I can do better lol.

Alright, thanks for your help! It's greatly appreciated.

Don't drill a hole, just use a small mirror to see it. To test it, just see if it will hold a deep well socket. You can do all of this with just the sensor removed.

1fatcat wrote:To test it, just see if it will hold a deep well socket

Wow does it pull hard, or is that just a handy round metal object? Also any ideas on how to remove the old magnet quickly and if I need to specifically position the new magnet?

If you have replaced the pickup, and you look in the hole with a mirror (shine a flashlight on the mirror to see better) and see the magnet in place in the cam gear, and it is firmly attached, the problem is more likely in the connector or the wiring to the cam sensor.

If you search for "code 41" you will find a lot of topics that specifically address this problem including links to Padgett's method for gluing a new magnet in place.

Some 3800's built in 1988 have a rectangular shaped magnet that bolts onto the cam gear rather than the newer plastic frame round magnet that snaps in place (from the back-side of the cam gear.) If you find a rectangular gear, I suggest you replace it with a new one by removing the front cover.

The position of the magnet is critical. It will not work properly unless it is where it supposed to be.

Removing the front cover of the engine to replace the gear "properly" is tedious, but is a lot less work than removing the fender and drilling holes.