Do some ECUs adjust for oil pressure?

SiRDOHC

Thread starter
Joined
Jan 20, 2012
Messages
48
Location
...
@SiRDOHC how far does your interest in your topic go??? If you really are curious, pick up a obd2 reader that can log your oil pressure, throttle angle, rpm, and cam angle. Plot them against each other using different grades of oil controlling parameters such as weather.

If these do not provide the speed you need for logging, maybe pick up a sn65hvd can board and a teensy 4.x and whip up something that logs your pid's at high speed.
I'm very interested in figuring this out. I have a veepak reader and Dash Command app. It comes down to finding the time to do the somewhat controlled runs with each viscosity. I will also take video of the runs. The videos alone should show the differences, especially at highway speeds where the engine does almost nothing to accelerate when in 5th gear running the lower viscosity oil forcing a downshift for even the slightest of passing. On the higher viscosity oil, everything breathes, intake and exhaust are louder and the car can get out of its own way.... of course fuel usage goes up significantly too when it is driving this way. I suppose the logs should show the amount of fuel being dumped into the equation as well.

Currently it's running the 0w20 which is slightly thicker due to residual from the last fill (a 0W30Pennzoil LX, Mobil 1 0W40 mix), but the effects of the lower viscosity are still felt. I will be dumping the 0w20 out for a 0w40 as soon as I get enough data logged, as I can't stand the way it drives with it in there even in the colder months. The only reason I put the 0w20 in again is because my neighbor gave me a jug of it, so I decided it to put it towards this semi scientific experiment. I'll try to capture it in a clean jug and re-purpose it somehow rather than send it for recycle.

To be honest, I was skeptical too that the changes were viscosity related, I thought that the intake runner swirl flaps were jammed open or something.
 
Last edited:
Joined
Oct 6, 2020
Messages
331
I'm very interested in figuring this out. I have a veepak reader and Dash Command app. It comes down to finding the time to do the somewhat controlled runs with each viscosity. I will also take video of the runs. The videos alone should show the differences, especially at highway speeds where the engine does almost nothing to accelerate when in 5th gear running the lower viscosity oil forcing a downshift for even the slightest of passing. On the higher viscosity oil, everything breathes, intake and exhaust are louder and the car can get out of its own way.... of course fuel usage goes up significantly too when it is driving this way. I suppose the logs should show the amount of fuel being dumped into the equation as well.

Currently it's running the 0w20 which is slightly thicker due to residual from the last fill (a 0W30Pennzoil LX, Mobil 1 0W40 mix), but the effects of the lower viscosity are still felt. I will be dumping the 0w20 out for a 0w40 as soon as I get enough data logged, as I can't stand the way it drives with it in there even in the colder months. The only reason I put the 0w20 in again is because my neighbor gave me a jug of it, so I decided it to put it towards this semi scientific experiment. I'll try to capture it in a clean jug and re-purpose it somehow rather than send it for recycle.

To be honest, I was skeptical too that the changes were viscosity related, I thought that the intake runner swirl flaps were jammed open or something.
Would be interesting if you can log and graph it over one another. Looking forward to your findings.
 
Joined
Oct 6, 2020
Messages
331
Here is the Mazda oil control. It is a two level oil pressure that even pulses to eliminate air in the oil system at start up.
Good info. Idk if this applies to the ops engine, but it may have answered @SC Maintenance question about oil pressure management under throttle and various inputs.

IMHO, oil pumps should be mechanical. Introducing more electrical components cause failure points. With electrics/electronics these days, they're quite common.

Anything for that .001 extra mpg to please Cafe and the green activists.
 
Joined
May 24, 2009
Messages
1,042
Location
So Cal
Good info. Idk if this applies to the ops engine, but it may have answered @SC Maintenance question about oil pressure management under throttle and various inputs.

IMHO, oil pumps should be mechanical. Introducing more electrical components cause failure points. With electrics/electronics these days, they're quite common.

Anything for that .001 extra mpg to please Cafe and the green activists.
What ops engine?
 
Joined
May 24, 2009
Messages
1,042
Location
So Cal
Car in question by the op(original poster) a 13 2 series Mazda. Does it have the same engine/oiling system for the 8nfo you posted to be relevant to his question or concern???
This is his question.

My question to everyone is have you experienced this with any other makes, models? I can only assume its an on the fly adjustment the ECU makes based on oil pressure which is now considerably higher with the heavier weight, euro oils.

He has a oil control solenoid on his Mazda for variable valve timing. I have a 2019 Mazda Miata BTW.
 

SiRDOHC

Thread starter
Joined
Jan 20, 2012
Messages
48
Location
...
My question to everyone is have you experienced this with any other makes, models? I can only assume its an on the fly adjustment the ECU makes based on oil pressure which is now considerably higher with the heavier weight, euro oils.

He has a oil control solenoid on his Mazda for variable valve timing. I have a 2019 Mazda Miata BTW.
@Bill W. Which Model Mazda with which engine and transmission?

Looking back, I have questions about other makes and models too. So many cars in this segment drove terrible in regards to throttle response and power cutting during shifting. The Ford Fiesta had a god awful rev hang condition, so bad that I immediately ruled the car out. Others like Versa, and the Fit had very pronounced rev hang as well. The mazda2 felt the most responsive, but perhaps the test drive wasn’t long enough to heat up and thin the oil, or maybe the factory fill was somehow more stout…. I’ll never know.

Here is a screenshot I took today, my foot pegged to the floor and for a second or two the engine load doesn’t go to 100%. With the higher viscosity the load value shot up to 100% immediately.
 

Attachments

  • E1A861B1-F68C-47C7-91F6-318FA434B560.jpg
    E1A861B1-F68C-47C7-91F6-318FA434B560.jpg
    100 KB · Views: 12
Joined
May 24, 2009
Messages
1,042
Location
So Cal
@Bill W. Which Model Mazda with which engine and transmission?

Looking back, I have questions about other makes and models too. So many cars in this segment drove terrible in regards to throttle response and power cutting during shifting. The Ford Fiesta had a god awful rev hang condition, so bad that I immediately ruled the car out. Others like Versa, and the Fit had very pronounced rev hang as well. The mazda2 felt the most responsive, but perhaps the test drive wasn’t long enough to heat up and thin the oil, or maybe the factory fill was somehow more stout…. I’ll never know.

Here is a screenshot I took today, my foot pegged to the floor and for a second or two the engine load doesn’t go to 100%. With the higher viscosity the load value shot up to 100% immediately.
2019 Miata RF GT-R. (upgrade suspension and LS Diff.) It does not have a oil pressure gauge but has VVT controlled by hydraulics and electric motor on the camshaft. Oil temperature always changes the oil pressure due to viscosity/temperature change. It has a ver. 5, 6 speed MT and the ND-2 engine that ups the HP to 181.
Hydraulic is exhaust.
Next page is the electric intake.
 
Last edited:
Joined
Oct 6, 2020
Messages
331
2019 Miata RF GT-R. (upgrade suspension and LS Diff.) It does not have a oil pressure gauge but has VVT controlled by hydraulics and electric motor on the camshaft. Oil temperature always changes the oil pressure due to viscosity/temperature change. It has a ver. 5, 6 speed MT and the ND-2 engine that ups the HP to 181.
Hydraulic is exhaust.
Next page is the electric intake.
That's a nice ride right there.
 
Joined
Oct 6, 2020
Messages
331
@SiRDOHC if you want to really log and you're not afraid to get into a bit of computers, here's something you or anyone might be interested in.

 
Top