Pull the cam sensor out. Bump the engine until the timing sprocket comes
around where the hole is in the timing cover and see if you can see or
feel the if the Magnet Interuptor is missing ( the part lists for $12 )
Its pressed into the sprocket. If the magnet is missing your cam sensor
isn't receiving the impulse signal, thus tripping code 41.
its a plastic coated manet that presses in from the back side of the
timing sprocket, You need to pull the timing chain off to replace it.
The magnet usually get struck to the side of the oil pan or is caught in
the timing cover.
Replaced mine in 2003 at 290,000 no more coode 41.
05 Park Avenue, 32,672
91 Bonneville LE 304,744