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Oil pressure

2002 cheverlot impale . the oil pressure switch keeps going bad and the diaphragm bust and oil comes out where the plug is. had to replace four in over a year . why and what make them go bad ?

What’s the actual oil pressure?
Maybe it is way too high.

had it check one time before was good . need to have it checked again.

Yes, unless that thing is an oil pressure sensor. They give a reading in proportion to the pressure.
Oil pressure switches usually just detect when it is low so they turn the dash light on. They don’t check when it is high.

What is the thickness of the oil you are running? 5W-20 or 5W-30 is what GM recommended.

If this car is used as a Taxi, you have the motor running lots of hours per day. If the actual oil pressure is checked and is about the normal 40-45lbs at 3,000 rpm then the problem is quality of the replacement part.

Get your next oil pressure switch from a GM dealer. It might cost more, but hopefully it is built better and will last longer.

yes . it is the sensor. i have been told nothing else can mess it up.

got one from GM it went bad . not used as a taxi will see about oil pressure .

Are you absolutely sure the plastic portion of the sensor isn’t cracked?
It’s VERY easy to overtighen the sensor when installing it and wind up cracking the plastic connector part of it, especially if you’re using a deep socket.

i will check if it is cracked. one more info , the sensor seem to go bad and shoot oil out from the plug end while I am traveling a distance.

What kind of tool are you using to install them?

I am using oil pressure switch socket 1-1/16 .

I see a couple of possibilities here.
Perhaps the sensors you’re using aren’t high quality.
Do the threads in the block and the sensor threads match perfectly?
You might be exerting sideways pressure on the plastic portion of the sensor while installing them.
It is very easy to damage a sensor that way. I’ve done it, but I realized my mistake before firing up the engine.
Is the socket you’re using deep enough? Trial fit a sensor into that socket.
Are you absolutely sure you’re not installing a knock sensor instead? This may sound idiotic, but some knock sensors look pretty similar to oil pressure sensors.

Come to think of it, that sender requires very little torque to properly install it.