Oil sending unit?

Tiny
DCHERRY
  • MEMBER
  • 2001 CHEVROLET S-10
Where is the oil sending unit located on the 4.3 vortec engine and how do I replace it
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Monday, October 12th, 2009 AT 8:35 AM

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Tiny
JDL
  • MECHANIC
  • 16,098 POSTS
Hello,

Ths distributor is located back by the distributor. Check out the diagrams (Below). Please let us know if you need anything else to get the problem fixed.
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Monday, October 12th, 2009 AT 10:48 AM
Tiny
CARPENTER38
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  • 1 POST
  • 1998 CHEVROLET S-10
  • 4 CYL
  • 2WD
  • MANUAL
  • 165,000 MILES
My fuel pump quit working.I've replaced it but still won't work. Looking through my book a bit closer I found that if the oil pressure switch goes out it will shut off power to the fuel pump. What I need to know is where the oil pressure switch is and the difficulty in changing it. Or might there be another problem? Fuses and relay is good.
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Wednesday, August 28th, 2019 AT 9:34 PM (Merged)
Tiny
RASMATAZ
  • MECHANIC
  • 75,992 POSTS
Do you hear the fuel pump come on for 2secs when key at run position. If not check fuse and fuel pump relay.

The fuel pump and oil pressure sending unit is located on right side of engine


https://www.2carpros.com/forum/automotive_pictures/12900_fpopsu_1.jpg

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Wednesday, August 28th, 2019 AT 9:34 PM (Merged)
Tiny
ERICDE
  • MEMBER
  • 8 POSTS
  • 1997 CHEVROLET S-10
Engine Mechanical problem
1997 Chevy S-10 4 cyl Two Wheel Drive Manual

My fuel pump has shut down and the truck wont start. I'll turn the key but can't hear any whirring from the fuel tank. I'm trying to check my bases before draining the tank and pulling the fuel pump. Would the oil pressure switch completely shut down the fuel pump or cut the pressure in some other way? I was told to CHECK the oil pressure switch, is there a way to check it or do I just replace it?
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Wednesday, August 28th, 2019 AT 9:34 PM (Merged)
Tiny
BLUELIGHTNIN6
  • MECHANIC
  • 16,542 POSTS
Oil pressure switch would not shut off fuel pump, however the fuel pump has a secondary route through the oil pressure switch. If the fuel pump relay goes out the pump will then run through the oil pressure switch after the engine gets oil pressure. This results in extended engine cranking time before the engine will start. Have you inspected all fuses, inertia switch (if equipped), relays and wiring before going in for a pump replacement?

Repalce your oil pressure sending unit. Thanks for using 2CarPros. Com!
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Wednesday, August 28th, 2019 AT 9:34 PM (Merged)
Tiny
K_RUSH2005
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  • 1 POST
  • 1997 CHEVROLET S-10
  • 6 CYL
  • 2WD
  • MANUAL
  • 13,000 MILES
I have a 97 s-10 4.3 we changed fuel pump and relay now truck wont start cranks over hard starts sometimes wondering if oil pressure switch is problem
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Wednesday, August 28th, 2019 AT 9:34 PM (Merged)
Tiny
RASMATAZ
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Check the fuel pump and oil pressure sending unit this is the one that powers the fuel pump when the engine fires up.
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Wednesday, August 28th, 2019 AT 9:34 PM (Merged)
Tiny
LCCARB
  • MEMBER
  • 4 POSTS
  • 1996 CHEVROLET S-10
  • 6 CYL
  • 2WD
  • AUTOMATIC
  • 200,000 MILES
I am having a problem w/ the oil pressure switch I have all ready put in a new one and I still get the same result. The oil pressure gauge is all the way to the right. I also replaced the fuel pump, ecm or computer, and the fuel relays. I replaced the fuel relays in the glove box I thought there may be fuel relays in another location but I could not find them, are there relays in another place besides the glove box? I drove the truck to my house a month ago and got it to start about a week ago but now it turns over but will not start. I know a good amount about cars but this one is relay giving me problems I cant figure out what I am missing. Do you know what could be causing the oil pressure gauge to just stay stuck to the right like this?
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Wednesday, August 28th, 2019 AT 9:34 PM (Merged)
Tiny
MHPAUTOS
  • MECHANIC
  • 31,938 POSTS
Hi there,

You will have to first check that the oil pressure is with in specs with a mechanical gauge, if that is ok, the problem will be in the wiring, start here.

Mark (mhpautos)
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Wednesday, August 28th, 2019 AT 9:34 PM (Merged)
Tiny
JEFF GRABLEWSKI
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  • 1996 CHEVROLET S-10
  • 4 CYL
  • 2WD
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Where is the oil pressure sending unit on my truck listed above (2.2)? Also, if it is bad would this make it show no pressure on the gauge?
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Wednesday, August 28th, 2019 AT 9:34 PM (Merged)
Tiny
RASMATAZ
  • MECHANIC
  • 75,992 POSTS
See below for location.

Check the oil pressure with a mechanical gauge, if normal replace the oil pressure switch. If abnormal could mean oil pump and engine bearing.
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Wednesday, August 28th, 2019 AT 9:34 PM (Merged)
Tiny
HMAC300
  • MECHANIC
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The sending unit is on the right rear side of your engine. If it were bad then you would show low or no oil pressure. But to be sure put a mechanical gauge on the engine to see if it is correct or not.
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Wednesday, August 28th, 2019 AT 9:34 PM (Merged)
Tiny
JSTRI
  • MEMBER
  • 4 POSTS
Where is the oil sending unit on my 91 s10 v6 4x4?
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Wednesday, August 28th, 2019 AT 9:34 PM (Merged)
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 42,549 POSTS
Hello,

Here is what the book says

Oil Pressure Switch (2.5L/4-151): RH Rear of Engine, Under Manifold
Oil Pressure Switch (2.8L/V6-173): Lower LH Side of Engine
Oil Pressure Switch (4.3L/V6-262): RH Rear of Engine

Please let us know if you need anything else to get the problem fixed.
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Wednesday, August 28th, 2019 AT 9:34 PM (Merged)
Tiny
ROBMACS10
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  • 1 POST
  • 1995 CHEVROLET S-10
  • 4 CYL
  • 2WD
  • MANUAL
  • 250,000 MILES
I have a Fuel Problem, Started when the fuel pump died. Replaced the pump, Cleaned up the ground. Pump does not come on at turn of key. Dad said could be oil pressure switch. Where is it and how do you check it? I have switch around the relays under the hood and in glove box. Did not help still no pump noise. Any suggestions?

Thank you.
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Wednesday, August 28th, 2019 AT 9:34 PM (Merged)
Tiny
BMRFIXIT
  • MECHANIC
  • 19,053 POSTS
When 1st key on fuel pump should come on for a min if not check wiring and connector plug
Fuel Pump/Oil Pressure Switch located On right side of engine, behind alternator.
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Wednesday, August 28th, 2019 AT 9:35 PM (Merged)
Tiny
BRYANPITTMAN
  • MEMBER
  • 4 POSTS
  • 1993 CHEVROLET S-10
  • 6 CYL
  • 2WD
  • MANUAL
I have a 1993 chevy s10 with a 2.8L motor in it. The oil pressure sensor blew out of the side of the motor and I replaced it. Now my question is how come when I replaced it and plugged it up up the fuel pump came on even when the ignition was off and the key out of it and didnt turn off until I unplugged the oil pressure sensor. Can someone please help me.
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Wednesday, August 28th, 2019 AT 9:35 PM (Merged)
Tiny
CARADIODOC
  • MECHANIC
  • 33,699 POSTS
Sounds like you have the wrong sending unit, it had two terminals reversed when it was made, or the plug is in backwards.

GM had some systems that ran the fuel pump off a terminal on the sending unit as a safety cutout. If the vehicle was in a crash that ruptured a fuel line, there would be no fuel pressure so the engine would stall. When it stalled, there would be no oil pressure so the switch in the sending unit would turn off and turn off the fuel pump. That would stop it from pumping raw fuel onto the ground.
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Wednesday, August 28th, 2019 AT 9:35 PM (Merged)
Tiny
BRYANPITTMAN
  • MEMBER
  • 4 POSTS
So why is the fuel pump coming on and staying on as long as tht sensor is plugged up even when the ignition is off? Also the truck wont even start since that oil pressure sensor went out and I replaced it.
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Wednesday, August 28th, 2019 AT 9:35 PM (Merged)
Tiny
WRENCHTECH
  • MECHANIC
  • 20,758 POSTS
I agree with doc on the fact that you likely have either a bad or the wrong oil sender. It is used as a redundant power supply for the fuel pump but it IS NOT a low pressure cut off. It does not have the ability to interrupt the fuel pump, it can only power it in the case of a relay failure.
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Wednesday, August 28th, 2019 AT 9:35 PM (Merged)

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