Oil Pump Slowly Dying?

[sen2two]

So I've noticed over the last week or two, my oil pressure gauge (stock) has been slowly getting lower. It was normally on the middle line (where the M is on normal) while cruising. It's now more towards the line just above the L. If I Rev the engine, the gauge dosn't seem to move. Which seems awkward to me. When the RPM'S climb rapidly, shouldn't the oil pressure also spike?

Is this common when a oil pump starts to die? Or could it possibly be the gauge or sending unit?

Also, this is my daily driver. I don't really want to pull the engine to do the pump if it is possible. I have access to a lift if I need it. Anyone here sneakily change out the oil pump without pulling the engine?

 

[DSB88GT]

I'm sure someone will chime in and tell you that the stock gauge isn't accurate, but I couldn't help but be concerned if mine started showing a lower reading. How many miles do you have? I'm curious how long oil pumps are expected to last.

 

[Dan_Soprano]

I would change the sending unit first. It's cheap and easy to do. You could also pull the distributor and a valve cover, and spin the oil pump drive shaft with a drill to verify you have good flow. There is a pressure relief valve in the pump that if the spring starts to get weak will result in lower oil pressure. I'd say before you go tearing down the engine, change then sending unit first. Second would be to hook up a mechanical gauge to the sending unit hole to verify. Changing the pump with the engine in the car could be done I suppose, but you would need to be able to jack the motor up quite a bit to get the oil pan off.

 

[sen2two]

So because it's good insurance anyways I purchased a new oil pump and sending unit.

But I realise now I didn't really check to see if there is a difference in the pumps for different 302 blocks. I have a non-roller 80-something block in my car. But the pump I ordered was for my 91 GT, a roller 302 obviously.

Anyone know for sure if the pumps are any different?

 

[jozsefsz]

I won't chime in and tell you that the gauge isn't accurate, I'll chime in and tell you that the stock gauge is just a glorified idiot-light on the 94-95's (which is where this question is posted). It's either 'Normal' or off ('Normal' if you have more than ~6psi). So what you're seeing is meaningless, other than perhaps a voltage drop through the sender, a battery / alternator voltage problem, or a ground issue. If this is about the Fox in your picture and not a 94-95, then carry on.

 

[sen2two]

Oops.... I did not realise I posted this in the 94-95 -95 section.

It is in fact for my Fox in the picture.