Camshaft position sensor

So, My SES is on, and has been on for a while.

It's the Camshaft Position Sensor.

1. I replaced the sensor.
2. Replaced the Water pump, because it was growling A LOT.
3. SES still on, I checked the wiring to the ECM and back, it was okay.
4. my mechanic checked it over and said that it was missing the magnet on the cam gear. He said he turned the car 360* and felt all over the gear where the sensor and magnet are supposed to contact.

WTF? He said it would be no big deal to run with out it. What do you guys think?

o.k. i had a bad camshaft position sensor and it turned out to be the plugs and wires JUST What happend to me

I had the same problem with a 92 Olds 88. It turned out to be a little magnet placed on the cam gear itself that broke and caused the SES to come on. I went ahead and replaced the Timing chain and gear set and also replaced the broken part. The SES turned off. BTW, I drove the car for almost 2 years with the part broken. So, driving without it will NOT hurt the motor at all! Hope this works!

if the ECU does not get a cam signal but is getting the crank signal (and I think certain other ones) it calculates cam position (this is made plausible because the timing is chain-driven not belt-driven).

Cam sensors are not all that expensive, why not just replace it before the weather's no longer good to work outside?

Albertj

When I had my '89 Riviera, I had the same thing happen to it after owning it for about 5 years. The magnet was no longer on the camshaft sprocket. I must say that I really didn't feel like tearing into the front of the engine and replacing parts. (OK I admit, for a mechanic (diesel R&E), I'm lazy when it comes to my cars...unless it really is necessary.)
I'm not proud of it, but I drove the car that way for over 2 years with the SES light on. I had slightly reduced fuel mileage (talking about 1 to 2 MPG in the city), but for as little as I drove the car anyway, it did not concern me too much. After all, I was eventually going to get around to replacing the failed parts, but it looks like that never came. Traded it in with the purchase of my '99. O well.

From researching back when I owned the '89, I seem to remember that the camshaft position circuit is basically signal for the Sequential Injection. Since mine was out, it could only fire Batch. I'm speculating that this had to do with my slight drop in fuel mileage around town. On the interstate or highway it still was capable of 28 to 30 MPG just as before.

Cheers

albertj wrote:

if the ECU does not get a cam signal but is getting the crank signal (and I think certain other ones) it calculates cam position (this is made plausible because the timing is chain-driven not belt-driven).

Cam sensors are not all that expensive, why not just replace it before the weather's no longer good to work outside?

Albertj

He said they did replace the sensor...

I would say it's okay to drive, as long as you don't go for any kind of performance driving. If you must leave it that way, take the SC belt off IMO.

Quote :

I would say it's okay to drive, as long as you don't go for any kind of performance driving. If you must leave it that way, take the SC belt off IMO.

The original poster's signature does not show the option of a supercharger.

My '89 still ran fine. The only little thing I noticed besides the slight drop in MPG was that the engine ran just slightly a little more rough at idle, and just off idle.

Oh whoops, I didn't even notice he has a '91. My bad. Anyway, should be okay.

Oh - sorry about the sensor comment.

If you can get to the spot, use engine cleaner on a q-tip to clean a place to glue on another magnet, then use a hi temp repair epoxy to stick it on. You can check polarity by asking a mechanic at a dealer or with a small compass as a junkyard, on a different 3800 (should not be hard to find one).

Albertj