Oil Pressure Sensor - P0521, P0522, P0523

[jrsherfy]

I (really my wife) have a 2007 GMC Yukon SLT. Her oil gauge has been "dancing" around. I have a CEL with the codes listed in the post description. The needle will peg out at 80 and drop to 0. The warning message comes on when the needle drops to 0. I checked the oil and it's fine. The codes point to the oil pressure sensor.

P0521 - Engine Oil Pressure Sensor
P0522 - Engine Oil Pressure Sensor Low Voltage
P0523 - Engine Oil Pressure Sensor Switch High Output

When I unplug the sensor and start the engine the gauge is at 0, so I think that points to a bad sensor and not a bad stepper motor.

I've searched old posts and the code descriptions. I'm going to replace the oil pressure sensor with the ACDelco D1846A GM Original Equipment Engine Oil Pressure Sensor.

I'm going to order the part on Amazon, because it's half the cost when compared to a part's store.

Have I missed anything?

 

[Doubeleive]

I would check the pressure coming out of the pump, if it is just a sensor consider your self lucky
could be sensor or clogged sensor screen (if it has one)
could be bad oil pump or seal on pump
beyond that it just gets ugly.

 

[swathdiver]

It could be your ECM but is probably the sensor. If you want to test the sensor:

Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the engine oil pressure (EOP) sensor.
2. Ignition OFF, test for less than 1.0 ohm between the low reference circuit terminal 1 and ground.
 If greater than the specified range, test the low reference circuit for an open/high resistance. If the
circuit tests normal, replace the ECM.
3. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal 2 and ground.
 If less than the specified range, test the 5-volt reference circuit for a short to ground or an open/high
resistance. If the circuit tests normal, replace the ECM.
 If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the
circuit tests normal, replace the ECM.
4. Verify the scan tool Engine Oil Pressure Sensor parameter is less than 8 kPa (1.2 psi).
 If greater than the specified range, test the signal circuit terminal 3 for a short to voltage or an
open/high resistance. If the circuit tests normal, replace the ECM.
5. Install a 3A fused jumper wire between the signal circuit terminal 3 and the 5-volt reference circuit
terminal 2. Verify the scan tool Engine Oil Pressure Sensor parameter is greater than 550 kPa (80 psi).
 If less than the specified range, test the signal circuit for a short to ground or an open/high
resistance. If the circuit tests normal, replace the ECM.
6. If all circuits test normal, test or replace the EOP sensor.

 

[HiHoeSilver]

I (really my wife) have a 2007 GMC Yukon SLT. Her oil gauge has been "dancing" around. I have a CEL with the codes listed in the post description. The needle will peg out at 80 and drop to 0. The warning message comes on when the needle drops to 0. I checked the oil and it's fine. The codes point to the oil pressure sensor.

P0521 - Engine Oil Pressure Sensor
P0522 - Engine Oil Pressure Sensor Low Voltage
P0523 - Engine Oil Pressure Sensor Switch High Output

When I unplug the sensor and start the engine the gauge is at 0, so I think that points to a bad sensor and not a bad stepper motor.

I've searched old posts and the code descriptions. I'm going to replace the oil pressure sensor with the ACDelco D1846A GM Original Equipment Engine Oil Pressure Sensor.

I'm going to order the part on Amazon, because it's half the cost when compared to a part's store.

Have I missed anything?

When you get the new sensor, see if it has a little plastic insert where the plug goes. Compare it to the old one. If the old one has it and the new one doesn't (usually the case), pull the insert from the old one and use it in the new one.

 

[jrsherfy]

Thanks for the responses.

@swathdiver - Thanks for check list. I'm a bit of a rookie with multi-meter stuff. I'll give it a try. If the ECM was bad, wouldn't there be other things going wrong with the truck's instruments.

@HiHoeSilver - Thanks for reminding me about the filter. That's something that could fall out when I'm taking the sensor off, and I wouldn't even know to watch for it.

 

[swathdiver]

Not necessarily, no.

 

[CobraKing]

@jrsherfy See the links below:

http://www.tahoeyukonforum.com/thre...pressure-by-07burb.62826/page-10#post-1072361

 

[jrsherfy]

It appears that the oil pressure sensor was what was needed. The truck's oil pressure is hovering around 40 again. It's not dancing around any longer.

This job took me a long time. I had to put on one socket piece at a time. First, I put the 1 1/16" socket head over the old sensor. Then, I used a hinged socket connector followed by a 6" extension. Finally, I placed the socket wrench into the 6" extension. I was able to loosen the old sensor. Then, one by one, I removed the pieces of the socket set along with the old sensor. I hand threaded in the new sensor. This is where things went sideways. Once I tightened the new sensor, I was unable to remove the socket. It was locked on the sensor just enough to keep me from being able to remove it with my hand. Anyway, I had to take the new sensor back out. I tied a washer to a piece of string and placed it in the socket, so that I could remove the socket easily once I put in the sensor for the second time. Also, I lubricated the inside of the 1 1/16" socket, so that it might more easily slide off the sensor. I was able to get the sensor back on and take the socket off.

The new issue is that the truck has P0174 and P0171 check engine codes. When my wife was driving it around the check engine illuminated. I think I messed up the PCV hose when I was trying to get to the sensor. I'll check it out tomorrow and keep you all posted.

 

[jrsherfy]

The P0171 and P0174 codes are gone. I made sure the PCV hose was snug. The codes have not returned.