SonnyinVA

hi guys,
i'm having the usual oil pressure sensor problem where it is pegged at 80 on the dash and 130 on the DIC... but with a twist. i've done the search and i've seen posts that say...

"Here is a quick test to see if its really your sensor going bad. Turn your ignition key on but DO NOT start the engine. When you turn the key, your gauges will cycle through their range and set to zero. If your sensor is going bad, you will see a pressure reading when the engine is off!"

ok... but mine reads 0 when off. is this "simple test" not true?

another issue is, the readings have now started to fluctuate back and forth between zero and max. should i be looking for a short somewhere? where do the wires go after they leave the switch? kinda hard to tell with the engine still in the car.

thanks guys!
sonny

muncie21

My second OP sensor behaved like this within a day of installation. Sometimes it would read max (80) other times zero and also swing widly back and forth, between 0 and 80. Of course my DIC was going crazy when this occured. Put a new OP sensor in and no problems since then. I was extra careful in tightening it to make sure I didn't crack/damage the plastic part of the sensor.

devo

"Here is a quick test to see if its really your sensor going bad. Turn your ignition key on but DO NOT start the engine. When you turn the key, your gauges will cycle through their range and set to zero. If your sensor is going bad, you will see a pressure reading when the engine is off!"


Hmmmm
If its pegged, maxed out, engine on or off the sensor is bad period.
mine has been this way over a month now.
Readings will fluctuate up and down but this is only a temporary condition soon it will just stay at 130 and not move.

molson

My car reads 8 psi with the key turned forward,and my sensor reads accurately.....I have had it verified with a mechanical guage.
I don't think that is an accurate way to test for a bad sensor...just my experience..

SonnyinVA

where did you hook the mechanical gauge up? did you take out the sensor and hook it up there? seems like that would be hard to do with the intake off, etc. and still be able to start the engine.

it's funny that you say that about your 2nd sensor doing that within a day. i just replaced the old sensor a while back and it worked fine for about 1 week and then it started reading higher and higher and then was pegged for a few weeks and then finally started doing this back and forth stuff... i am planning on putting in a new sensor this weekend, and i'd like to hook up a mechanical gauge while i am at it just to verify that i do have good pressure. where can i get a mechanical gauge, by the way?

SonnyinVA

i am also getting a DTC of 522 by the way...

P0522 Engine Oil Pressure Sensor Circuit Low Voltage

i don't guess this changes anything? should expect this, or does this point to some other issue such as a short or wiring issue?

muncie21

Higher OP reading is an open circuit, low reading is shorted. You should also be getting the Service Engine Soon message. All my codes went away after my 3rd sensor. Hoping this one will last a while. On a positive note, I'm getting better (faster) at removing the intake now. First time it took about 2 hours. Second time had it done in about an hour.

molson

The dealership took my oil filter off and installed their gauge then ran the car briefly.It read the same as my sender and DIC.
I am only speaking from my experience,I am by no means an expert.
It is a pretty easy way to verify your gauge reading.
My manual states to check: for a mis-routed harness,rubbed through wire insulation ora broken wire inside the insulation if code 522 is present.If this doesn't work it gets pretty complicated from there.
Good luck

Raider2

Just logged on to see if I could find any information regarding a pegged out oil pressure gauge on a '99 convertible I just traded for and came across your post. Perfect timing. Today is the first day I've driven the car without the salesman in the car and I hadn't noticed the oil pressure reading 80 and the DIC showing 129. From what you guys are saying, its a common problem with the sensor. I'll have the dealership deal with it next week. THANK YOU. I thought I had BIG problems.

SonnyinVA

i changed out my sensor on sat and now everything is fine! hopefully it lasts this time.

i had the intake off and the new sensor on in about 25 minutes... i'm getting WAY too good at this... i put it all back together and would have been done in less than an hour, but the guy at GM that decided to put that little short piece of $#!^ vacuum hose at the rear of the intake needs to be slapped... apparently it must have come off while i was putting the intake back together, cuz when i went to do my test-fire, i could hear it whistling... so another 45 mins later... all done.