Cam Sensor_code reset?

The sensor itself isn't the problem on the 3800. The problem is that there is a magnet mounted in a plastic bushing in a hole on the cam sprocket and with age and heat the plastic becomes brittle. Eventually one day you mash the gas and the high RPM causes enough centrifugal force to break the plastic and send the magnet flying inside the timing cover.

The fix is of course to replace the magnet but as the bushing goes in from the back of the sprocket the official fix involves removing the timing cover and the sprocket.

The worst that will happen driving it this way is that the engine is operating in batch injection mode instead of sequential and that may cause reduced economy, power, and smoothness. Other than that since the MIL is already on it can't alert you to any other problems or failures.

Hope this isn't a repost:

The sensor itself isn't the problem on the 3800. The problem is that there is a magnet mounted in a plastic bushing in a hole on the cam sprocket and with age and heat the plastic becomes brittle. Eventually one day you mash the gas and the high RPM causes enough centrifugal force to break the plastic and send the magnet flying inside the timing cover.

The fix is of course to replace the magnet but as the bushing goes in from the back of the sprocket the official fix involves removing the timing cover and the sprocket.

The worst that will happen driving it this way is that the engine is operating in batch injection mode instead of sequential and that may cause reduced economy, power, and smoothness. Other than that since the MIL is already on it can't alert you to any other problems or failures.

Daniel,

One other issue he'll face - if he lives in an area that requires smog testing his Buick will fail for having the MIL on while the engine is running.

To the original poster - if you do decide to get the magnet replaced you're looking at a repair bill in the $800 range - you basically have to pull the front of the engine apart to do this job (I've done more than a few over the years).

If you are going to go to that expense, go ahead and have the timing gear set & chain replaced. You're already going to have 90% of the labor anyway and the timing gear/chain set will add about $75 to the bill. You're getting to the mileage where the original chain is probably stretched a bit and the plastic teeth on that cam drive gear are getting rounded-off and will become prone to "slipping a tooth".

Best Regards, Bill Bowen Sacramento, CA

Most places where they are using the CEL light only do testing on ODBII vehicles, and don't bother with anything prior to 1996. At least in New England areas he'd be OK if he just pulled the CEL light!

Not in NY. They connect the unit to the OBDII connector. It then runs through a test cycle that turns the light on/off and if it doesn't come on you fail, if the computer says the light has been triggered ON by the ECM, you fail, If the ECM says it has some monitors that are not set due to lack of drive cycles, you fail.

If he is downstate where they run the dyno testing with a tailpipe sniffer it's even worse.

Yes, just what I said... That care DOES NOT HAVE an odbii connector so they can't run their machine on it.

I don't know the NY rules but in NH anything older than 96 is exempt. This is because they (0lder than 96) don't have ODBII. So are medium and heavy duty trucks.

Dyno testing sucks.

In California, even in areas that don't do IM-240 testing (dyno) the FIRST test that is done is to turn the ignition switch to "ON" and see if the CEL/MIL illuminates. The engine is then started and you look to see if the CEL extingushes. If EITHER part of this test fails, the car fails.

Cars model years 1975 & earlier are exempt here - it used to be a "rolling 30 years" window but that was fixed at 1975 about 5 years ago.

Bill Bowenhat is an aut