Thread: Trouble History With Camshaft Position Sensor

Im doing a poll to see how many of you have had trouble with your Camshaft Position Sensor. Specifically I want to collect information on multiple sensor replacements.

Please, PLEASE, be serious and keep things on topic. I joke around a lot because I want to keep things light and fun, but I need the information to be as accurate as possible and all the participation that can be had.

ive never had to change mine, but i know how to if i ever need to.

as i recall, the symptoms are that the car starts, but dies shortly thereafter and you cant keep it running.

Yep, in some cases you will not even be able to start it.

Bump. You mean to tell me that Bio was the only one that had any input on this?

From my experience on the forums, the crank position sensor is more likely to go bad than the cam position sensor. I believe, but don't quote me, that if the cam position sensor goes bad, the car will still run, but timing advance won't work. So your car will be very sluggish. But a bad crank position sensor will not let the car run at all.

And I have never replaced either.

Originally Posted by Zef_66

But a bad crank position sensor will not let the car run at all.

You are right to a point. If the side of the CPS that controls the tach signal goes bad, it may stall or you'll loose traction control but it will in many cases will still run. If the side that controls spark goes out, then obviously the engine wont run.

Originally Posted by SyntheticShield

You are right to a point. If the side of the CPS that controls the tach signal goes bad, it may stall or you'll loose traction control but it will in many cases will still run. If the side that controls spark goes out, then obviously the engine wont run.

If you want to move this to another thread, feel free to keep this one clean.

I am not electronic guru or anything, but I would image the crank position sensor just measures the position of the crank at certain times and reports them to the PCM. From there, the PCM will tell the tach what RPM to read. Also, the PCM will tell the ICM when to fire what cylinder based on the appropriate spark tables. And the traction control is also controlled through the PCM based on the measured and controlled sprak. Again, don't know for sure, but my guess is that spark, TC, and tach are all controlled by the same sensor reading of the CPS and when that sensor goes bad, everything gets fubared.

I had a diagram somewhere that showed the layout of the CPS and its signals. All of them, if I remember correctly went directly to the Ignition Control Module, then from there to the PCM. I'll see if I can dig it up.

What made it odd is that the CPS and Cam sensor operated off 10vdc which was really weird and I couldnt figure out how they were stepping that down from the normal system voltage until I saw it went through the ICM which apparently is providing some voltage regulation. But there are two distinct signals provided by the CPS triggered by the interrupters on the back of the harmnonic balancer.

Originally Posted by SyntheticShield

I had a diagram somewhere that showed the layout of the CPS and its signals. All of them, if I remember correctly went directly to the Ignition Control Module, then from there to the PCM. I'll see if I can dig it up.

What made it odd is that the CPS and Cam sensor operated off 10vdc which was really weird and I couldnt figure out how they were stepping that down from the normal system voltage until I saw it went through the ICM which apparently is providing some voltage regulation. But there are two distinct signals provided by the CPS triggered by the interrupters on the back of the harmnonic balancer.

Good to know. I never really looked into it. And since you looked at the diagrams, I will take your word for it.

Nah, dont take my word for it, Im just as fallible as anyone and as subject to making mistakes as anyone. But I did post up the diagrams, they just were in another thread somewhere dealing with a Coolant Sensor issue.

I wonder if this is my problem. Click to this thread to see what i wrote.

http://www.grandprixforums.net/f18/i...use-14267.html

i've only had to replace mine once so far

Knock on wood...I've never had to replace the CPS either, but damn I am on the 3rd Motor LOL

ive havent had to replace mine yet. i just bought the car in november and have put about $3000 in repairs into it, so who knows with this pile of sh**, i might be replacing mine next week