Two oil sensors?

[dc7432]

I have a 87 350 TBI with a sensor above the oil filter and a two prong sensor next to the distributor? Which one runs the gauge on the dash? The connector from the wiring harness on the intake manifold is broken where can is buy a new one? Thanks in advance

[bd]

The oil pressure switch next to the distributor provides back-up power to the in-tank fuel pump in case the fuel pump relay fails.  The oil pressure gauge is operated by the single-prong sensor above the oil filter.

Which connector?  The OPS near the distributor uses AC Delco P/N PT1951 (see image).

[dc7432]

Thats it thanks for the info

[Irish_Alley]

The oil pressure switch next to the distributor provides back-up power to the in-tank fuel pump in case the fuel pump relay fails.you wont be stranded on the side of the road or lose brakes (cause the switch is still giving you power, now once you try to restart it it will take longer than normal cause you have to build oil pressure back up to energize the switch) And kicks on the (idiot) light if the pressure drops below 4psi???  The oil pressure gauge is operated by the single-prong  sender above the oil filter.

Which connector?  The OPS near the distributor uses AC Delco P/N PT1951 (see image).

is this correct bd?

[bd]

@ dc7432 - Your welcome!

@ Irish -

[If the fuel pump relay fails] you wont be stranded on the side of the road or lose brakes (cause the [oil pressure switch will continue to provide power to the fuel pump], now once you try to restart it it will take longer than normal cause you have to build oil pressure back up to [activate the switch and energize the fuel pump]).  And the switch kicks on the (idiot) light if the pressure drops below 4psi.

is this correct bd?

          Now, it is.


And...

The oil pressure gauge is operated by the single-prong sender above the oil filter.

Really?

From the dictionary...

sensor:
a mechanical device sensitive to light, temperature, radiation level, mechanical energy or the like that transmits a signal to a measuring or control instrument.

sender:
a transmitter of electric pulses.

Either word is perfectly acceptable and often used interchangeably in manuals.

[Irish_Alley]

i understand what your saying about sensor and sender but flashing back to my autozone days if you look up oil pressure sensor nothing will show up but if you look up oil pressure sender then you get a sender (now i know just because autozone says something doesnt make it right). but in my mind its a fuel tank sending unit not a fuel tank sensor unit because it sends the signal to a gauge. a sensor sends it to the ECU ie oxygen senor and coolant sensor/switch (for ecu) vs a coolant temperature sender (for gauge) the coolant sensor wont work the gauge and the sender wont work for the  ecu.

what i was saying about brakes is if your engine dies you will lose power brakes, now you will still have brakes but not like you had when the engine was running.

now to me (ALSO) a switch has a Closed position and a open, so if the oil pressure needs to be high enough to trip it then this is the open position? so if its low or not running it will be closed and will trip the idiot light.

bd im not challenging you or anything just trying to clear up the confusion i have

[bd]

There is nothing wrong about anything you posted, except for context.  Technically, you are correct - a switch is digital - it is either on or off.  The oil pressure "switch" at the back of the intake that backs up the fuel pump relay has no control over any dash light - not even the SES light.  That OP switch is wired in parallel with the relay points that supply the fuel pump and serves the sole purpose of powering the pump if the relay fails.  If you unplug the relay, the engine will still start and run following extended cranking sufficient to build oil pressure. 

The problem with terminology is that it is commonly misused.  Every OEM has its own unique approach to nomenclature.  Within any given OEM, the service manual transcribers use different nomenclature than the parts division.  In addition, official terminology changes every couple of years.  You want to take a magic carpet ride, start looking for a "module" in a GM parts book.  One year it will be listed as a "module," the next year, a "controller," after that, a "board," then a "control," then a "switch," then a "timer," and so on, until you become so dizzy you forgot what you were trying to find.  "Switches" are "senders" are "sensors" are "controls" are....  "A" = "A" = "A;" everything is the same.  It's crazy!  After searching for a while you might even begin to think the part doesn't actually exist, except for the fact that you have it in your hand.  Chrysler labels some of their w/w pulse boards as "governors."  Try to pull that one out of your hat if you haven't run across it before.  It depends on who wrote the particular reference that year.

Hence, to be successful, the solution is to become familiar with a very broad group of descriptive terms and not get stuck or insistent on minute details.  As long as you know the various terms that are "possible," eventually you'll strike on the correct label in the proper context and attain what you want.  The main objective is to be able to effectively communicate a specific concept to someone who is familiar with the 'correct term' as listed in the parts book.  Any word (which is just a symbol for something) is useful only when it conveys sufficient meaning to communicate an idea to someone, who can then put it to constructive use.  Make sense?  Don't get hung up on the nomenclature.

[Irish_Alley]

gotcha