Buick Lesabre Camshaft Postion Sensor Keeps Going Bad

The 1990 Buick 3800 Lesabre was a car my father purchased 10 years before his death and I have repainted and restored it to like new and drive it daily. Problem is that the cam position sensor I have replaced 3 times. We have checked the magnet on the timing gear and it is in place. After the first replacement it worked for a week before failing again. I keep getting a check engine light with codes for it.

Reply: Do you have an engine light on your Buick now and what are the codes? What are the code numbers?

Yes the engine light is on again but I do not remember the code number. I had a free computer scan done at a shop and can't find the papers but i do remember it was for the camshaft position sensor for sure.

buick lesabre

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A trouble code number would be very helpful. Well i would assume your are sure the code is for the camshaft sensor. So if you have replaced the sensor several times and you are sure the magnet on the cam gear is good you may have a wiring problem. Wiggle the wiring harness around with the engine running to see if you can cause the engine light to come on. It is also possible you are dealing with a bad batch of sensors. Are you getting the same brand sensor from the same parts store?

Yes Your correct. I have ordered a new male plug and once again verified the magnet is there. Is there a way I can detect voltage or check for a signal (power to this)? I do know how to use a multimeter.

Does the sensor show any signs of being scrapped by the magnet? If the magnet is loose it will rub but that is hard to determine. Try a very small needle nose pliers to see if you can grab and move it.

Anyway to check the sensor? No, it was very clean with no signs of rubbing.

OK. The sensor itself creates a voltage signal. There are electrical tests that can be done to check the output of the sensor, but being that it is a 1990 it may take me some time to find them since i would have to look at some of my old paper service manuals. If you would like to leave me your e-mail, maybe i can get you that info later tonight or tomorrow.

Thanks Yes.

I am in Chicago. One thing you can do also is after the new sensor is installed and the car is running fine without a check engine light start moving around the wiring harness to see if you can get the light to come on. You may not have bad sensors at all, just a wiring problem. Follow the harness as far along as you can.

Look for an email from us- it may have a picture attachment, so depending on your email setting, it may go to your spam.

In my email just tag it Buick and even with a attachment I can receive. Yep I been in Chicago I live in Cleveland and raised my family.
I have copied this info and looking forward.
Thanks man and have a good evening.

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