ECM not seeing the oil pressure sensor

[Desert_Rob]

I have a 2010 SS with hot heads and cam, I bought the car recently in great shape. The factory oil pressure gauge started reading zero after a few months, but no ECM low oil pressure alarm telling me to kill the car immediately, so I thought it's after the ECM , the sensor is likely still good. I changed the sensor, same result. No pressure showing at the factory gauge, but still no ECM alarm telling me to shut it off due to no oil pressure. I built a test rig with a mechanical gauge to use at the oil pressure sensor port, removed the sensor to test it. the test was good, great oil pressure as I expected. The thing I don't understand is that I still did not get an ECM low oil pressure alarm, even with the sensor not installed during the test. I let the motor warm up, still no alarm. If anyone has insight on what it might be I would appreciate it. I don't know if the previous owner might have done something to disable it, so I am going to install a permanent mechanical gauge from the block off cover near the oil filter to be sure. Good thing is, after I got the oil pressure sensor installed after the test, the factory gauge is working again. Would appreciate thoughts on the ECM oil pressure alarm possible causes of it not functioning.

[EasternPine]

Originally Posted by Desert_Rob

I have a 2010 SS with hot heads and cam, I bought the car recently in great shape. The factory oil pressure gauge started reading zero after a few months, but no ECM low oil pressure alarm telling me to kill the car immediately, so I thought it's after the ECM , the sensor is likely still good. I changed the sensor, same result. No pressure showing at the factory gauge, but still no ECM alarm telling me to shut it off due to no oil pressure. I built a test rig with a mechanical gauge to use at the oil pressure sensor port, removed the sensor to test it. the test was good, great oil pressure as I expected. The thing I don't understand is that I still did not get an ECM low oil pressure alarm, even with the sensor not installed during the test. I let the motor warm up, still no alarm. If anyone has insight on what it might be I would appreciate it. I don't know if the previous owner might have done something to disable it, so I am going to install a permanent mechanical gauge from the block off cover near the oil filter to be sure. Good thing is, after I got the oil pressure sensor installed after the test, the factory gauge is working again. Would appreciate thoughts on the ECM oil pressure alarm possible causes of it not functioning.

The only variable you changed is disconnecting and reconnecting the sensor plug and the sensor itself.

Check the contacts.

Always half split the issue you're troubleshooting. Either you have a good input or a bad output and since you changed the sensor itself and verified the input to be good so that only leaves the harness connector onward.

[Desert_Rob]

it's working perfectly now. My question is why did the ecm not send the alarm when the pressure was at zero, even if it was a faulty sensor? I think the previous owner somehow turned off the computer alarm for low oil pressure but I don't have access to the programmer or tune information. Was hoping someone that is smarter than I am on this issue could tell me if that is possible. I am still installing the mechanical gauge permanent for that reason. I fully expect the problem with the factory oil pressure gauge to surface again and can ignore it as needed since the ecm alarm won't be bothering me since it doesn't work.
The car has had the engine tuned several times, has been modified quite a bit for more hp, there's no telling what the last programmer bypassed.

[EasternPine]

Originally Posted by Desert_Rob

it's working perfectly now. My question is why did the ecm not send the alarm when the pressure was at zero, even if it was a faulty sensor? I think the previous owner somehow turned off the computer alarm for low oil pressure but I don't have access to the programmer or tune information. Was hoping someone that is smarter than I am on this issue could tell me if that is possible. I am still installing the mechanical gauge permanent for that reason. I fully expect the problem with the factory oil pressure gauge to surface again and can ignore it as needed since the ecm alarm won't be bothering me since it doesn't work.
The car has had the engine tuned several times, has been modified quite a bit for more hp, there's no telling what the last programmer bypassed.

I guess I'm kind of lost here comprehending, this built in gauge you mention are you referring to the 4 pack or the oil pressure BAR readout in the DIC?


DTC for the sensor itself is factory disabled, but others will trip if the values are too high or low which would happen if the sensor did go bad or if the wiring or connectors became damaged, oxidized or that would otherwise tamper with voltage inputs going into the ECM e.g. bad/floating ground, open circuit or shorting. The fact that you had no MIL means the ECM isn't the problem, it's highly likely past the ECU. Goes back to good input/bad output so whatever is meant to transport/display the ECU's MIL.

Attached is the factory default settings for DTCs: P0521-P0523 (P0520 is made redundant by the other DTCs)


Do you have anything else running on the CAN-Bus? Anything plugged into the OBD2 port by any chance? Did you disconnect the battery to replace the sensor? If so, it could be that it works now since you reset all the modules and allowed them to test their connections to each other via the harness.

I don't claim anything as absolutely certain but I am interested in knowing how this happened as much as you are.

[Desert_Rob]

I'm pretty much an idiot with this. I bought the car three months ago, got a great deal out of Dallas, drove it, bought it. I don't know anything about ECM , DIC, or engine programming. It is the factory gauge cluster oil pressure gauge that was reading zero until I messed with it. I didn't unplug the battery, this was the third time I've had that sensor off, did each time without disconnecting the battery. Both of the other times the pressure stayed at zero on the factory gauge. After I ran the mechanical pressure test and reassembled did everything actually work. Nothing that I did would have fixed this in my opinion but I only work on much older hot rods, this is the first fuel injected race car I've ever owned, I will be getting the programmer setup to see it all myself. The DIC does not currently show any oil pressure bracket, but I probably don't know what I'm looking at

[1JEWLDSSRS]

Originally Posted by Desert_Rob

I'm pretty much an idiot with this. I bought the car three months ago, got a great deal out of Dallas, drove it, bought it. I don't know anything about ECM , DIC, or engine programming. It is the factory gauge cluster oil pressure gauge that was reading zero until I messed with it. I didn't unplug the battery, this was the third time I've had that sensor off, did each time without disconnecting the battery. Both of the other times the pressure stayed at zero on the factory gauge. After I ran the mechanical pressure test and reassembled did everything actually work. Nothing that I did would have fixed this in my opinion but I only work on much older hot rods, this is the first fuel injected race car I've ever owned, I will be getting the programmer setup to see it all myself. The DIC does not currently show any oil pressure bracket, but I probably don't know what I'm looking at

On a 2010 the DIC will not show any oil pressure info, only the 4 pack gauges will show anything, or an aftermarket gauge hooked up to the OBD port to monitor that info from the ECU..

[Desert_Rob]

Thank you for letting me know that, I was worried that something had been removed. Do you know if the low oil pressure alarm not functioning is normal for this car? 6 speed manual with 6.2, thanks again for helping me figure this out. Had a feeling the forum would connect me with people that know this a lot better than I ever will. Thanks to all

[gtstorey]

Do you have a warning light for oil pressure that comes on key on, engine off? Check your owner's manual to see what indication it should give for low oil pressure.

[1JEWLDSSRS]

Originally Posted by Desert_Rob

Thank you for letting me know that, I was worried that something had been removed. Do you know if the low oil pressure alarm not functioning is normal for this car? 6 speed manual with 6.2, thanks again for helping me figure this out. Had a feeling the forum would connect me with people that know this a lot better than I ever will. Thanks to all

Yeah only the 2014-15's show the oil pressure in the DIC screen. I'm not aware of any "low oil pressure" alarm's on these Camaros. And according to all this, there is a "low oil level" warning light to warn you when you are low on oil, but nothing I saw as a warning about the pressure. I don't thing there is one, or it would have shown on the DIC. That's where the gauge comes into play. Any of the other guys that have had, and posted a "zero" oil pressure issue have only noticed it on the're gauge.

https://dashboardwarninglights.com/chevrolet-camaro/

[gtstorey]

https://assets.gm.com/manuals/chevro...aro_owners.pdf

Page 4-33

Oil Pressure Low – Stop
Engine
This message displays if low oil
pressure levels occur. Stop the
vehicle as soon as safely possible
and do not operate it until the cause
of the low oil pressure has been
corrected. Check the oil as soon as
possible and have your vehicle
serviced by your dealer/retailer

[1JEWLDSSRS]

Originally Posted by gtstorey

https://assets.gm.com/manuals/chevro...aro_owners.pdf

Page 4-33

Oil Pressure Low – Stop
Engine
This message displays if low oil
pressure levels occur. Stop the
vehicle as soon as safely possible
and do not operate it until the cause
of the low oil pressure has been
corrected. Check the oil as soon as
possible and have your vehicle
serviced by your dealer/retailer

Well there we go. I don't think anyone who has had this problem has ever said anything about that message being shown..Hmmm. Thanks GT...

[Desert_Rob]

I need to get a laptop setup to answer you lol, Easter Pine what do you recommend? and thanks for all the info

[EasternPine]

Originally Posted by Desert_Rob

I need to get a laptop setup to answer you lol, Easter Pine what do you recommend? and thanks for all the info

I personally bought mine while I was deployed in Africa so its overkill as far as a diagnostic/tuning platform goes as it was my only source of entertainment in the desert.

Anything with a Intel I5 or the AMD equalivalent or higher will do the job. At least 16GB or memory, and at least a USB C port.


As for the software HPTuners, you'll need a MVPI 4 and 2 credits(3 if you mess with the fuel pump which don't bother with unlocking unless you have a lot of time to learn as you can brick the Fuel Pump module) which cost me like 600 dollars but it allows me to do beginner tunes for my small bolt on mods as well as let's me utilize remote tunes between dyno sessions.


It's not a full fledged service scanner like an Autel, it's targeted towards the ECM, TCM and the FPCM and can manipulate those where your normal scan tool cannot.