91 PA code 41 cam sensor question

I can't get rid of code 41, cam sensor. I have installed a new magnet and new cam sensor, and tested the circuits involved. I have also subsitituted a Power Control Module (PCM) and ignition module purchased at a salvage yard. The car runs perfectly whether the cam sensor is connected or not, and whether I am using my original ECM and ignition module or those from the salvage yard. I am getting a steady 11,25 volts at pin ba12 on the PCM with the engine running. I Just want to get rid of the "service engine soon" light. I've disconnected the battery many times for several minutes, but after five seconds with the engine running the code always comes back. Any ideas?

On the 91, code 41 could also indicate a crank sensor problem. Here is a post on that subject. This is for a 95, however the same applies to the 91.

http://www.automotiveforums.com/vbulletin/showthread.php?t=217926&page=1&pp=15&highlight=crank+position+sensor+replacement
Crank position sensor - '95 LeSabre Dies Without Warning

HotZ28,
Thanks much for the link. There are a lot of ideas for me to consider. My problem pales in comparision to those described within that thread. I suspect something else is causing my cam sensor code, maybe a grounding problem or the crank sensor. The timing chain could be a factor, although my car runs smoothly, so I doubt it. My PA has 160k miles so I may change the timing chain as a precaution. Will put in a new crank sensor if I do that.

If you have 160K and never changed the timing set, I would defiantly do that. I changed mine at 140K and it was sloppy loose with a broken magnet in the cam gear. I also replaced the water pump, chain tensioner, crank sensor and cam sensor. Those parts are cheap considering the labor required to go back and replace one of them later!

I will change the timing chain and crank sensor as my next step. Do you have any recommendations regarding this project? It looks like getting the balancer off and on is the hardest part. Did you change the sprockets as well?

I overhauled my transmission a couple years ago, and was surprised by the large amount of slack in the drive chain. Am sure my cam chain is equally loose.

The balancer is a PITA and yes, I put the complete timing set in. The cam sprocket has the little magnet in it to trigger the cam sensor and they are known to break and fall out. If the magnet is broken and only part of it is still in the gear, you will get a code 41 also.

Some of the plastic housing of my original magnet was missing, but replacing it didn't help. Apparently it was working, even with some of the plastic gone. I rechecked the replacement magnet recently using a small mirror, and it is perfectly seated, so I have discounted this as the reason for my code 41. Can the damper be removed with a standard puller, like I could borrow from Auto Zone?

The balancer bolt holds the balancer in place, it is not a press fit like some of them. Removing the bolt is a PITA unless you have the right tools. I used a C/P ¾ in drive impact wrench that develops over 500 ft. lbs. of torque @ 150 psig. It was easy with that! You might want to consider renting one at your local tool rental store; otherwise you will have to do it manually. If you choose the manual method, you need a deep-well six point impact socket, pull bar and a cheater bar. (Twelve point thin wall sockets have been known to break or slip on the bolt) You will also need to have someone hold the flywheel with a large screwdriver wedged in the teeth to hold the crank from turning while you loosen the bolt. (You can also purchase or rent a flywheel holding tool). I have seen people remove the hood and stand on top of the engine with a six food cheater bar to break the bolt loose. :eek7:
Once the bolt is removed, the balancer will slide off of the crank, (with a little pry bar) or small balancer puller. Be sure to reinstall the bolt to the correct torque specs and recheck the crank sensor gap when installed.

:cheers:

Thanks much for the advice. I will go straight to the impact wrench solution. Didn't know about a
"crank sensor gap". The instuctions I have indicate positioning the crankshaft sensor it with a special tool, J-37089. Is the positioning of the crankshaft sensor variable?

Yes, you will need to set the gap. You will get the instructions with the crank sensor and depending on what brand you buy, you might even get the .020 shim to set the gap. If not, go to Auto Zone or a competitor and get a brass feeler gauge set with the correct size for the job.

Went to Auto Zone and read the instructions on the crank sensor. The gap refers to clearance between the damper vanes and the sensor. I assume this is to prevent the damper from rubbing against the sensor. Is this the reason for the gap? There was no shim in the package. Would the shim be used to keep the damper from seating to close to the sensor?

If you have too much clearance it will not trigger and if it is too close it may hit the vanes and destroy the sensor. I have read on some other post that people buying crank sensors from Auto Zone found that they were defective after installing them! I hope you have better luck! :sunglasse


Here it is:

http://www.automotiveforums.com/vbulletin/showthread.php?t=437566&highlight=auto+zone

Here is another thread on the crank sensor subject that may help also;

http://www.automotiveforums.com/vbulletin/showthread.php?t=434151&page=1&pp=15

Thanks for the info. I will buy the crank sensor from Advance Auto. Their parts are a little more expensive than Auto Zone, but in this case it is probably worth it. Now, I'm starting to wonder if the cam sensor I bought at Auto Zone is working properly. I may get a couple cam sensors from the salvage yard to do some more checking.

My 91 gave me those codes a while back. Got the crank sensor replaced with no change in SES light. Inspected cam sensor and found magnet missing. Paid about $300 to get them to go in and replace the magnet, but while they were in there, had the timing chain, etc. and water pump replaced.

I feel it was money well spent. Unlike all the money ive blown on broken motor mounts :mad: