Intermittent Code 41

[larryscope]

OK, I promise no more posts today...

To put it mildly, I understand that the 3800 engine (this one's an L) has an issue with the camshaft magnet failing or falling off. Has this been known to cause an intermittent SES code 41, or only a steady one? At first it was intermittent but now it comes on some time after you start driving and stays on, but never comes on right when you start driving.

[Jim Adams]

code 41 might be the ignition module as well under the coils this would only start to act dumb or come on after the coil get hot aswell,,,this also might be your problem with the cruising speed shudder,,it may be misfireing when it levels off at cruising speed

[larryscope]

Originally Posted by Jim Adams

code 41 might be the ignition module as well under the coils this would only start to act dumb or come on after the coil get hot aswell,,,this also might be your problem with the cruising speed shudder,,it may be misfireing when it levels off at cruising speed

Hmmm...I know that one day the SES DID come on at the same time as the shudder kicked in. However the shudder's been around for maybe as long as a couple of years (but probably getting worse now)...the car doesn't get driven that often, especially on the highway, so it wasn't a high priority to get fixed.

I did notice that on a recent highway trip the car got rather poor gas mileage from what I remember in the past...would this help to differentiate between a true cam sensor problem or an ignition module problem? Would the spark plugs, or some other component like the oxygen sensor, show some evidence either way?

Is the ignition module serviceable, and would it show any evidence? BTW, it's a 'type II' module (what the service manual called it), the one with three cylindrical formations on the cover.

[Hansnet]

Originally Posted by larryscope

Hmmm...I know that one day the SES DID come on at the same time as the shudder kicked in. However the shudder's been around for maybe as long as a couple of years (but probably getting worse now)...the car doesn't get driven that often, especially on the highway, so it wasn't a high priority to get fixed.

I did notice that on a recent highway trip the car got rather poor gas mileage from what I remember in the past...would this help to differentiate between a true cam sensor problem or an ignition module problem? Would the spark plugs, or some other component like the oxygen sensor, show some evidence either way?

Is the ignition module serviceable, and would it show any evidence? BTW, it's a 'type II' module (what the service manual called it), the one with three cylindrical formations on the cover.

I saw a coilpack with ICM for 10 bucks on ebay a few times now.

I'd say do all your plugs (oem 41-601 Delcos) and wires (NOT bosch) and replace coils and ICM. Maybe check the TPS voltage as well.

[larryscope]

Not surprisingly, pulled off the cam sensor and found that the magnet was heading south. There wasn't much left of it; a 'kernel' surrounded by lots of gunk.

I suppose it would make sense that a failing magnet could cause an intermittent code. I read that it takes five seconds of no signal from the cam sensor to trigger the SES - that can be a lot of revs!

Plan to put a new one in next couple of days. We'll see if that does it.