'07 + DIY Oil Pressure Sensor/Switch Replacement - 20 minutes!
 

UPDATE: If you're convinced that the sensor/switch is the culprit and are ready to jump in and replace, I strongly suggest that you read this post and some of the related posts in this thread.
The low pressure reading may not be from a bad sensor!

After some weird, erratic behavior, my '07 Suburban's oil pressure needle pegged at 80/3 o'clock on the gauge; then a few days later at 0/9 o'clock. It subsequently threw a code resulting in a non-clearable MIL.
Pretty compelling evidence that there was a fault in the switch/sensor, the connection or wiring. I concluded a bad switch/sensor.
Not being able to pass MD emissions with a hard code and not knowing the oil pressure, I knew I had to fix this (also it's my wife's car :rolleyes:). I ordered a new

AC Delco sensor/switch from Amazon

AC Delco sensor/switch from Amazon

and started to check into the cost of having the repair done at the dealership, or a good GM mechanic. Couldn't be too bad, right?
Wrong.
Everywhere I checked, starting with the dealer, quoted me $500 and up. All said that the intake had to be removed in order to access the $50 sensor & replace it. Ouch.
Being a DIY'er and a skeptic when it comes to dealer service, I decided to look into this myself. The sensor isn't visible from any angle when standing next to the engine bay. It isn't visible when lying on top of the engine. A chipmunk crawling back there could see it however. It's located waaay back there, screwed in to the top of the block vertically, behind the intake, roughly centered below the firewall cowl.
After some fumbling around, standing on the driver's side, leaning against the fender, I was able to touch it.
Okay, I thought, there has to be some angle where a DIY'er can get to this.
There is.*
It isn't pretty but it can be done. In 20 minutes!
You'll need the following, or else you won't be able to do this:

• A new switch/sensor
• Familiarity of how the plug goes into the sensor, and how the tab would snap on and off. Feel the tab on the sensor with your eyes closed because you won't be seeing any part of this plug at any time.
• A deep socket to clear the plastic top of the switch. I used a 27mm which was perfect
• An extension of the right height. No less, no more. Mine was a 5" extension.
• A ratcheting socket wrench. I used a 1/2 drive.
• A blanket, old lounge cushion or small dog bed
• A little patience
• A lot of dexterity
• Humility (you'll be crouched over the engine. What will your neighbors think?)

The total height of the socket, extension and top of the wrench are critical. My socket is 3"; the extension 5". With all snapped together, the total was 8 1/2" from the tip of the socket to the top of the wrench. Again this is critical as you have very limited space back there.
How to do it:

• Be prepared to do this job in one session. You don't want to remove the sensor and leave the opening exposed for any period of time.
• Start with a cool engine. You'll be crouched over it for 20 minutes.
• Pop off the intake cover from its rubber plugs by lifting the front & tilting up.
• Take your blanket/dog bed/cushion and lay it over the the driver's side of the engine
• In you go. You'll need your wrench/extension/socket handy
• While hunched over the engine, head almost touching the hood/firewall, reach back between the engine & firewall, going in on the driver's side of center.
• You'll find the connector harness as it plugs into the switch with a little lock tab.
• Find the tab and gently pry it upward at the same time, lifting the plug..not by the wires, but by the plug.
• When that pops off, grab your socket and worm it in under the fuel rail (I think) and snug it on the sensor
• Take the extension, settle it into the socket and snap in place.
• Snap the wrench into the socket and ratchet that baby out.
• Carefully bring your new sensor to the opening with your hand, not snugged into the socket.
• Hand thread the sensor into the threaded opening, taking care not to cross thread. Hand tighten as much as you can. Mine started to thread easily.
• Go in with the socket and settle it on the new sensor, then the extension, etc. Install the new sensor in reverse order, remembering to reattach and snap lock the harness plug.
• Using a OBD II tool, reset your code Key On, Engine Off.
• Start her up and watch that gauge come alive and the light stay off:D

This is where the patience comes in:
Take great care not to drop your socket, wrench or extension, as you'll need to be climbing under your vehicle to retrieve it if you're lucky and it falls through.Of course these can be retrieved with a magnet. Not the case with the sensor! It's aluminum, so a magnet isn't going to help. Dropping a tool or the sensor will surely turn a 20 minute job into a several hour ordeal.

*Ham fisted, impatient, DIY'ers with some degree of pride need not apply. Tell your mechanic that this absolutely can be done with the right socket/extension combo, and good hands - without pulling the intake, and he can do it in 1/2 hour and be all zipped up in less than one labor hour.

Very nice! and thanks for the detailed how to DIY:cool:

Oil pressure switch
 

Thanks for the instruction. Looks like 2007 year has a longevity problem with switch. You would think they would put in a place easier to reach.
Did you use any treading tape for sealing or self seal? Jc

Oil sensor switch 2007 avalance
 

Ok you need to add three Advil to the formula. I also bought a oil switch socket that helps removal and reset. Much patience needed and small to medium hands. Do not attempt if large belly or fat hands since yoga and meditation should be practiced prior to attempt.
Mission accomplished in three hours not 20 minutes. Can be done but as stated must be persistent . Jc

Great write up! My suburban just started doing this last night so it looks like I'll need to do this job

Just did it.
 

Thanks for the write up. I am an oil change and brake pad type guy, but just completed this one in less than 20. I followed your suggestions , but tied some fishing line around my socket and the sensor, so I could fish them out if dropped. Never had to though. Harness popped right off when clip released. Able to feel threaded hole when finger starting the new sensor. Plus it was -5 degrees in mn today so I made sure the engine was warm while I was mounting her:)

Timely!
 

How timely, just got on here to find just this and there it was, right on top of the heap!


Was on the road, sans time and tools. Gauge at 0 with CEL on. Concerned enough that I had the Burb towed to Dealership. Diagnosed at Dealership and when I found out what the problem was, passed on them doing it, but they quoted it at $368.15 (parts and labor) plus tax and shop chg. Probably right at four bills out the door.


Bought part on eBay, $35.00 shipped. Now getting ready to do the work! Thanks for the great write up, very nimble fingers, but very large hands. Hope they don't prevent me from gaining access! lol


MORAV

Fantastic!!! My son and I were headed out on an extended trip when the oil pressure gauge went to zero in his 2007 Suburban. He had been told the sensor was faulty and had gotten a replacement "just in case." We found this forum, used the step by step from MORAV and in 30 minutes, in the dark, my son changed out the sensor!!! Great step by step!! and it saved him a few hundred bucks on top of it.


Kent and Keir

Did this today. Can't thank this thread and this one, https://chevroletforum.com/forum/tah...n-39757/page4/, enough for the pictures. What a pain. I'm reading oil pressure again.

My question: does the light reset after x number of driving cycles or do I have to get the code cleared? 9/2@6:30 PM -code light went out by itself: two short start/stops; one twenty minute drive; 4th start -light was out.

Thanks,
Peter
Kensington, MD

Peter, thanks for the follow up that the forum worked for you, following up on a fix or a repair is what makes the forum work!:cool:

Something to make this easier
 

These switches can be a pain, but two things that make it much easier is to disconnect the fuel line from the fuel rail and buy or borrow a wheel step. This is a platform that hangs on your tire so you don't have to crawl on top of your engine. Don't forget to relieve the pressure on the fuel line before removal.

thanks this helped me out alot!

while you have the switch out, replace the screen underneath it. it could be fill will crud causing the problem in the first place. If you can get it out without damaging it, you could wash it out. I prefer replacement.

I have not done this or seen where it is (the screen) but I'll ask the question anyway.. once the sensor is out, can you get enough access to the screen to hit it with carb cleaner to clean it out and then do an oil change afterward to remove the contaminated oil ?

the small cup shaped screen sits just below the sensor. Lift it up and out to remove it for cleaning. carb cleaner will work fine.
I have seen dirt and metal shavings on this screen. It will be loaded with crud for those who continuously run the olm to 0%.

That's a good question. One that I was wondering about as well.

Now, more than a year and many thousand miles later, with synthetic and earlier change intervals - I haven't had a repeat 'failed sensor' code. Pressure consistent and running as normal.
I'm now even more confident that in my Burb's case the apparent sensor failure wasn't a failure but a sludge at the screen issue.

Oil Pressure Sensor
 

I replaced the sensor about 1 week ago. Had no problems out of it until today. Started the vehicle got to the end ml of my street and the check engine light, oil pressure light, and stabilitrak light came on. All these lights came on the first time as well. The code that came up on the last engine reading with P0521 which was Oil Pressure Sensor High Voltage. Any information on any possible fix for this problem?

year, model, engine, new body style or old, afm or non afm?


-did you check the oil level?
-did you install an aftermarket part or gm?
-did you check the sensor filter screen?
-any engine knocking when the low pressure light/message occurs?

Add to that
-what type of oil has been used (synthetic or conventional)?
-what have your oil change intervals been?

2007 Chevy Tahoe 5.3L 4x4
Checked the oil level it was good, the new part was aftermarket, couldn't get to the screen filter, no knocking and noises when the light is on, conventional oil (high mileage), and about 3000-3500 miles

since you do not have a knocking noise and the oil level and condition are good...it is more likely to be a sensor reading issue an not a true low oil pressure condition.

I have seen bad aftermarket sensors...haven't seen many wiring problems but it should be properly tested to rule out.


imo I would replace the screen first. its cheap.

Thanks, but...
 

Thanks, but can't take the credit, wasn't my DIY!

Knowing what the issue was, and it now being one of my wife's infrequently driven dailies, just got around to this. Also needed an oil pan gasket (web-$19.32), also which I knew about, but didn't get around to either. In this case pressure was sitting a flat 0.

I've got a hook-up thru one of the Service Writers at a Dealership and pay cash to have a lot of things done with one of the respective line techs at the Dealership. Bought both parts ahead of time and had them both installed $200 cash. Wish I had read about the screen, I would have had that done also (cheap insurance). Do things when I can, have the talent, but little time, and currently at eight vehicles between my wife and myself. Just put a set of new shoes all the way around (not at the Dealer) and had the alignment done while it was on the service floor.

The bad news, since my original posting...
WTF, motor mounts were bad (I had suspected) and bought at pair that a Tech had in his stash and he installed for cheap. A "Service Suspension System" message popped up... WTF, $501.35 retail for the pump (found it for $215 OEM New), and $455.60 EACH!!! for the shocks (still searching), which we won't know leak until the pump is replaced. Good god! And now the cluster lights (the white lettering and the blue shift indicator and message center) are dimming up and down on their own, and the rheostat switch works and doesn't work but can't get them upon bright. They do that on their own, sporadically. One of my Tech buddies says he can tell where the failure is with the computer, as it could be the control module and not the switch. This all to be done when I get back from a Thanksgiving trip to my Daughter's in CO. Maybe get around to the impact sensor and the level sensor upgrades for the alarm system while I've got it in, so my buddy at the Dealership can tune them into the control module while he's got the computer running. lol

Back on the subject of oil pressure, all of a sudden, I have what was described in the first post (bouncing back and forth from 0-80), happening on my '03 2500 Burb 6.0L, except no CEL, just a warning signal every time it drops to 0. Gonna' do the sending unit and the filter screen this time, on this one. Have to look around some threads, maybe they placed it in a better location on the 6.0L :)

Hope I didn't hijack the thread too bad!

Everyone...
Have a Great Holiday Season!

Morav

great post! i hope its as DIY as you make it sound!

It is extremely important to use OEM switch for replacement. I learned this the hard way! I believe the root cause of the switch failure is the Active Fuel management and the pressure relief valve in the oil pan. If the relief valve doesn't function correctly, I think this causes the switch failure. The best money I have spent is $200 for the deactivation module from Range. Plug it in to your OBDII port and it turns the AFM off. The first thing I noticed was the elimination of excessive oil consumption (@186k miles). The next thing I noticed was, believe it or not, improved fuel mileage from 15.7 to 16.3 mpg. No AFM, no switch failure.

Also, to get the screen out, use a dental pick.

Tigerfan,
If you're looking to replace the oil pressure sensor because of a low pressure reading and a subsequent OBD code indicating a bad sensor, you might want to read this thread before you dive in (literally), as the issue might not be a bad sensor, but a blocked/dirty screen as farmit is suggesting. If you do end up replacing the sensor, definitely clean the screen/filter WYIT.

Low Oil Pressure Switch Sending Unit Silverado 2003
 

Hey guys, I have the same issue (Low Oil Pressure Switch Sending Unit Silverado 2003, alarm keeps going off, normally pegged out at 80 but fluctuates down to 0 at times) and know for a fact it is the switch. I had the engine pressure checked and it is fine. I travel a lot and am not sure when I have the time to replace the switch. Is there any way that one knows of to disengage the alarm for the Low Oil Pressure Alarm so it won't drive me crazy? I can't seem to find that alarm fuse if there is one.

I think I have this problem,,,,, all of a sudden,,, oil alarm sounded off,, message no / low oil pressure,,, gauge at zero,,,,,, YIKES !!!! But oil on dipstick, and no rattle or common noises from a motor with true "0" oil pressure,,,,,,,,,,,,,,. Oil gauge will move up a little then fall back, with each restart. So,,,, looks like a a sensor failure, yes ?

That would be a yes, Good luck with your project.

Thank you everyone here for the info on this sensor,, my mechanic buddy changed it for me. For a small job,,, it is not real easy,,,, and brought some nasty phrases, but the next one will be easier,,,,,,. He did not remove anything, except the engine cover, so that added to the nasty phrases a little. But no more low oil alarm, 60psi oil pressure,,, all is good,,,,,,,,,,,,,,, thanks again,,,,,

Hey PtownBubba

We’re sorry to hear that you’re experiencing concerns with your vehicle. Please feel free to send us a private message if we can be of any assistance. We’re always glad to help.

Cecil J.
Chevrolet Customer Care

Fixed it in 45 mins.
 

I just bought a 2007 Vortec Max with the LS2 motor with 148k miles on it, well the oil sensor light came on and it showed 0 on the pressure gauge. Well I did some checking around and found this thread, which helped me very much. Well needless to say I went and picked up the sensor at o'riellys well after about 45 mins I had it taken apart and put back together, the gauge jumped up to about 20 instantly. I also did some calling around about how low the pressure was and the mechanic said that 700-1000 Rpm it would only have about 6 psi and at 4000 Rpm it would only have about 24 psi.

Thank you guys guys very much for the help.

Hey Roger, congrats on getting the job done your way instead of the dealer's way!
I don't know much about the '07 Vortec Max engine and how many components/systems it shares with the 5.3 found in the Suburban, but since you recently bought this truck and may not know its full maintenance history, you might want to read my post here just for the hell of it....and to give you extra peace of mind. The thread describes low pressure readings in the 5.3L engine not related to a bad switch/sensor or a bad sensor connection.

I read this threat last night and completed the installation this morning. Literally took me about 1 hour to do and that was me going super slow. Thanks for posting this.

Also, remember that after you get the sensor out that there is a filter in there as well. You will need to fish it out with a hanger or a screw ( I used a screw). The filter costs 5.00 at advanced auto. Its worth replacing that too as well because I only want to replace this one.

I called Midas and inquired about how much it would cost for them to do it and they said $396 plus tax. Luckily I had already did it, I just wanted to see how much I saved.

Wow, even if the part(s) were marked up to $75 (which is a lot), that's unbelievable amount of labor for this job. Especially for a mechanic who has done this job before. I can't fathom this being more than 1 hour flat rate for a mechanic.

From repairpal: "The average cost for an oil pressure sensor replacement is between $113 and $151. Labor costs are estimated between $81 and $103 while parts are priced between $32 and $48. Estimate does not include taxes and fees."

But this site shows the dealer wanting $500 for the job https://www.fixmyoldride.com/Chevy-e...-pressure.html

I believe that the model-specific service manual calls for removal of the intake, due to the inaccessibility of the sensor - at least from GM's standpoint. That would explain the high estimate.