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Hello,

One of the most important readings that you could have is oil temperature. It gives you an indication of when the viscosity of your oil is in the right range, when the thermally activated additives are ready to go, and also gives you some "clarification" of if your driving style is permitting the oil to get up to temperature to drive off fuel dilution and water.

It seems to me that OBDII systems should be reading that parameter. It also seems to me that the SGII X-gauge shouldbe able to give us this information.

Has anybody been able to extract it? Searching this forum doesnt give me any info, and its likely not a reading that many consider early in the game... It is, however, of key importance...

Thanks,

JMH

Shouldn't that be at least approximately what your coolant temp is?

It could be nice to see Oil temp and/or pressure.

unfortunately those parameters do not appear to be available via standard obd-ii.
here is good list of reference
http://en.wikipedia.org/wiki/OBD-II_PIDs

manufactures can add there own unpublished obd-ii codes, but again unfortunately you would need to find IF there is a code for your can then program an x-gauge.
unfortunately manufactures are NOT open with those things, so the info is hard to get.

now fortunately missing that info is not as much a problem for hypermilers as someone towing a heavy load. and towing tyranny oil temp would also be great.

I feel your pain. I live in North Dakota and it can get down to -40º in the winter time. I would really love to see oil temp and transmission fluid temp. Unfortunately we can't have what doesn't exist.
I have a block heater but I would really like to know how much of that heat transfers to the oil (I doubt it is very much).

Gives me an interesting idea along the same lines as a grill block.
Insulation for the oil pan.

That pan is often fully exposed under the car, you could potentially be loosing a lot of heat through the oil pan.

But… Before I would go trying to raise my engine temp by keeping the oil warm I would a way to keep an eye on oil pressure and temp. at least pressure, assuming the oil pump is going to deliver less oil pressure when the oil is hot.

It is a bit of a guess, but I don't think most cars have a sensor for the oil temperature. The OBDII port can't provide data which is not sensed. After market oil temperature guages are available from a number of sources. The easiest installation is to use the sensor type which substitutes for the oil drain plug. VDO had such a guage at one time, back when I was building race cars.

Oil temperature roughly approximates water temperature with some lag. Since the oil is routed in passages which are close to water passages, the oil will eventually reach the same approximate temperature. The quick way to heat oil is to put a lot of bearing load on the engine, like running it at full power. Of course, that is counterproductive for a hypermiler.

I did find, at one time, a heating pad which could be bonded onto the bottom of the oil pan to rapidly heat the oil. Played around with it some to get oil hot before the start of races, until the authorities decided that wasn't legal ;-)

Yes, generally oil temp sensors aren't put on cars, because coolant temp approximates oil temp. Oil does heat faster than coolant. Really, oil is the primary coolant, given that it reduces friction AND takes heat away via the oil pan. The water based coolant is secondary. We get a good indication of potential heat related problems when the water based coolant isn't cooling enough. Heads/head gaskets are the usual heat related failure, and water based coolant sensors give us a better picture of what is happening in that area.

My semi tractor has an engine oil temp gauge, a transmission oil temperature gauge, and differential oil temperature gauges for each drive axle. They do reflect how hard I'm working the truck, but only barely. Most variance in temperature is related to ambient temperature. The only time my temp really climbed was when a bearing failed in the transmission. So the benefit was diagnostic, not operations.

Keith

Keith, just curious, does your semi have an OBDII port?

No. Truck manufacturers aren't under the '96 Fed Mandate to standardize reader ports.

Keith, I still think that in most lightly loaded automotive applications, the engine oil temperature will lag the coolant temperature. The water temperature is regulated by a thermostat, while oil temperature is not regulated in most cars - in my experience. I certainly agree that ambient temperature has a strong effect, and as you say load is a very strong determinant. But, remember that hypermilers operate at very low average loads. Synthetics, as most folks run, will take even longer to warm since there is less frictional loss at the bearing surfaces.

It would be nice to run a study and get a verifiable answer, but with few engine oil temperature sensors in service, I doubt we will get any data on lightly loaded automotive applications. The only actual experience I have is with dyno testing of racing engines. Before a dyno "pull" the operator wants the engine oil temperature up to racing levels, around 240 degrees. Obviously the operator wants to start each pull at a standard temperature, since oil temperature has an effect on horsepower - potentially allowing a source of horsepower measurement error. I always found that it was virtually impossible to get the engine oil up to that temperature without running a couple of minutes of max load exercising of the engine. In fact, it was difficult to quickly get oil temperature much above 120-140 degrees without hard exercising of the engine.

Wow, I would be surprised to find out that there isn't an oil pressure sensor somewhere. The oil pressure idiot light must be getting its info from a pressure sensor. Maybe this sensor is really crude and only detects low pressures.

Maybe the sensor does read gradations of pressure but an alert-light-only goes on low readings??

Charlie

Charlie, it's the oil TEMPERATURE sensor that is missing from most cars. I'd suspect that virtually all cars have an oil pressure sensor :-)

jimepting, why would anyone really be concerned with oil temp?
True, you would like it to get up to operating temp fairly quickly, but other than a grill block and engine heater there really isn't much you can do about oil temp.

In so far as anyone is concerned with oil breakdown from excess temps-modern water cooled vehicles in good condition don't overcook their oil. If the coolant temp is ok(coolant system working properly), the oil temp is ok!

It might be interesting to know, but it wouldn't change anything.Oil pressure on the other hand can be a big deal in either direction.

Charlie

Charlie, I don't really think many folks get very concerned about oil temperature in street engines. For the most part, there isn't much one can do about it, as you say - so I'm agreeing ;-) On high performance cars with oil coolers, one might block the cooler. But in the fuel efficient cars that most folks here drive, including me, there are no oil coolers to block. I suppose that the desire is to get the oil hot asap so that there are fewer viscous losses. These losses are measurable on an engine dynomometer.

But, non the less, the conversation (thread) started with a desire to measure the oil temperature. I didn't start the thread :-)

why would anyone really be concerned with oil temp?

My main concern is because of the extreme cold climate that I live in. The oil turns to a molasses like consistency and I am concerned about the lubricating properties. Maybe I am just paranoid.

http://www.youtube.com/watch?v=gKtxqf5OFTU

Oh,I get it-cold climates.It is 75+ here today outside New Orleans,so too thick, too cold oil isn't much of a concern.

You could put some sort of heating element-like your block heater- on the underside of the oil pan-guess that has been mentioned.
Heck, the oil pan is aluminum maybe you could turn it into a frying pan. Just plumb/plug a couple of wires from the battery into it, and heat the whole bottom of the oil pan.Just put an in cab switch in it,give it a minute or two-hot oil.

Might be smarter to check Finland or Russia etc. Those folks there deal with this sort of ting all the time.They must have add on gadgets that can be attached to the oil pan.

Whay don't you just tap a sensor- maybe a coolant sensor-into the oil pan? Liquid temp is liquid temp? Should be cheap enough.

Charlie

My main concern is because of the extreme cold climate that I live in. The oil turns to a molasses like consistency and I am concerned about the lubricating properties. Maybe I am just paranoid.

http://www.youtube.com/watch?v=gKtxqf5OFTU

That video makes me feel better about the mobile 1 I paid extra for.

I found this while looking up Block Heater info.
Use this for Extream cold oil care? No thanks I will buy Mobile 1. :D
:biglol:
Block_heater
During the dawn of aviation in pre-war Northern Canada, aviators flew with flight engineers who were responsible for preparing the radial engines for shutdown and startup in order to mitigate the effects of sub-zero temperatures. The flight engineer was responsible for draining the oil into buckets at night, and pre-heating both the engine and the buckets of oil using a blanket wrapped around the engine and a device known as a blow pot, essentially, a kerosene jet-heater used several hours prior to flight

One simple option is to install a dip stick heater. I am hesitant to buy one though because it only puts out 90watts and I have a hard time believing that it would do a whole lot. Maybe it would raise the temperature a couple of degrees.

http://www.amazon.com/Kats-15200-Dipstick-Style-Heater/dp/B000BO74DG/ref=sr_1_13?ie=UTF8&s=automotive&qid=1228011032&sr=8-13

oisiaa-
Don't know how extreme your temps get, but I think your money would be better spent on changing to a full synthetic if you haven't already. Synthetic would also be good in your trans and differential in such cold temps.
I've started cars at -30F :no engine heater, conventional oil. There definately can be valve train noise for 10-20 seconds before the oil starts pumping. But gentle driving/warm up ensures the demands of the engine don't exceed the ability of the oil to provide lubrication.
The most miserable cold weather experience I've had- starting a bus at -29F. The manual trans two hands to shift for 2-3 miles. There was no way to warm it up without driving the bus. (no kerosene heater on hand:))

Keith

jimepting, why would anyone really be concerned with oil temp?
True, you would like it to get up to operating temp fairly quickly, but other than a grill block and engine heater there really isn't much you can do about oil temp.

In so far as anyone is concerned with oil breakdown from excess temps-modern water cooled vehicles in good condition don't overcook their oil. If the coolant temp is ok(coolant system working properly), the oil temp is ok!

It might be interesting to know, but it wouldn't change anything.Oil pressure on the other hand can be a big deal in either direction.

Charlie

The reality is that oil temperature does approximate water temperature with about a 20 mile/minute lag. I have an oil temperature gauge in my 91 BMW, and it indicates that often the oil temperature does not even reach the water temprature... sometimes it doesnt even reach 120F!

This is a major issue. More and more vehicles these days are dealing with severe fuel dilution issues, and water in the oil can also contribute to wear and effect the life of the oil.

At the same time, it is poor practice to fully load an engine prior to it being up to full temperature - not full water temperature. There is a difference, and until the oil is at, say 100C, the viscosity is not necessarily within the right range w.r.t. bearing clearances. Metallic parts may have a higher C.T.E., and thus not be fully, optimally protected.

Additionally, in more of the modern, cramped and areodynamic engine compartments, with highly power dense engines, you are seeing oil temperatures that are far higher than water temperatures! 230-260F is more than doable in hot weather under high load. Knowing this helps to optimize lubricant selection, as it is generally advisable at that point to go to a higher viscosity for operation, if it is routine!

THere is lots that plays into it. Apparently my saab has an oil temperature sensor somewhere... it may be readable, but I dont have a clue how to figure it out. Any thoughts??? I dont exactly have experience playing with OBDII/CANbus.

Thanks,

JMH

The reality is that oil temperature does approximate water temperature with about a 20 mile/minute lag. I have an oil temperature gauge in my 91 BMW, and it indicates that often the oil temperature does not even reach the water temprature... sometimes it doesnt even reach 120F!

This is a major issue. More and more vehicles these days are dealing with severe fuel dilution issues, and water in the oil can also contribute to wear and effect the life of the oil.

At the same time, it is poor practice to fully load an engine prior to it being up to full temperature - not full water temperature. There is a difference, and until the oil is at, say 100C, the viscosity is not necessarily within the right range w.r.t. bearing clearances. Metallic parts may have a higher C.T.E., and thus not be fully, optimally protected.

Additionally, in more of the modern, cramped and areodynamic engine compartments, with highly power dense engines, you are seeing oil temperatures that are far higher than water temperatures! 230-260F is more than doable in hot weather under high load. Knowing this helps to optimize lubricant selection, as it is generally advisable at that point to go to a higher viscosity for operation, if it is routine!

THere is lots that plays into it. Apparently my saab has an oil temperature sensor somewhere... it may be readable, but I dont have a clue how to figure it out. Any thoughts??? I dont exactly have experience playing with OBDII/CANbus.

Thanks,

JMH
If your vehicle does have an oil temp sensor, it should have a PID available for both the sensor voltage and actual temperature. For a Ford the oil temp mode $22 PID is $0907. I don't know if either of my GMs have an oil temp sensor, but I can check. I would assume a Saab would be the same as a GM.

Bump -- just to see if any more info had been obtained on OBD-II and oil temp....

Plenty of add on gauges out there if you need to read engine oil temperature.
http://images.google.ca/images?hl=en&q=engine+oil+temperature+gauge&btnG=Search+Images&gbv=2

The Jeep I was in Friday & Sat had one from the factory and an oil pressure gauge, just as inaccurate as any factory gauge though, no way it was up to 100 degrees right after cranking that straight 6 engine (literally 2 seconds from first start up).

I am new to programming this tool... But, for VPW protocol you can try $1602.