Cold weather use K20A3 oil choice

Bmsluite

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Uhh no. The engine management system keeps the idle speed higher to warm the engine so the emission control system can operate. If your engine speed is remaining elevated then the engine is either not warming up or it doesn’t think that it is. It will also inhibit the shift points of the transmission for the same reason.
It's a manual trans sooooo....
 
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It's a manual trans sooooo....
Okay well everything I said except for the upshift inhibit. Understand? Either way it’s tied to coolant temperature (or the sensed temperature) not because the engine is trying to pump oil around.

Most engines have at least two coolant temperature sensors, one for the gauge or light and the other for the ECM. Are both working?
 
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K20A3 engine with 100k miles

So I have an Acura Rsx Type S which is my wife's winter beater (pretty fun winter beater if you ask me). I change oil every 6 months whether it gets used or not. I am probably throwing away oil but it is what it is.

95% of it's use is in Chicago winter through stop and go traffic commuting 5 days a week. Other than that it just sits.

It rev hangs for a looooonnnnnggg time when you start it when it's any sort of cold outside. I have notice this is temperature related.

I have been using PUP 5W30 but want to throw in a 0W so I don't have wait forever for it to heat up.

Only options I really see are M1 0w30 and M1 0w40. Wondering if I should go the 0w40 because of engine age or stick to 0w30 since it's cold weather use only.

Also open to any other suggestions and will easily change my mind when logical data is presented.
Use the Widman operational viscosity calculator. 0W-40 will be thicker than a 5W-30 for most temperatures; so, it will make the problem worse.


For example, at −10 ℃, M1 FS 0W-40 will have 1,050 cSt and PP 5W-30 will have 880 cSt.

M1 AFE 0W-30 is actually the thickest with 1,100 cSt.

M1 5W-30 is 1,010 cSt.

PUP 5W-30 is 888 cSt.

So, PP 5W-30 or PUP 5W-30 seem to be the best choices.
 
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Use the Widman operational viscosity calculator. 0W-40 will be thicker than a 5W-30 for most temperatures; so, it will make the problem worse.
Wait, a lower viscosity oil heats up faster than a higher viscosity? In what universe?

Not that it really matters anyway in terms of coolant temperature which is what is being referenced here.
 
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Wait, a lower viscosity oil heats up faster than a higher viscosity? In what universe?

Not that it really matters anyway in terms of coolant temperature which is what is being referenced here.
0W-40 is a higher viscosity than 5W-30. However, it has lower cold-cranking (CCS) and cold-pumping (MRV) viscosities at extreme temperatures.
 
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Okay and how does that affect how it shear heats in operation?
That will be a secondary effect. You can't expect that a thicker oil will run thinner than a thinner oil because it gets heated more because it is thicker and has more friction. The engine will probably warm up faster than the oil anyway.
 
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That will be a secondary effect. You can't expect that a thicker oil will run thinner than a thinner oil because it gets heated more because it is thicker and has more friction. The engine will probably warm up faster than the oil anyway.
What? You’re doing quite a dance here around which oil heats up faster in operation. It is always a higher viscosity oil unless physics has suddenly taken a vacation. So your statement above that a higher viscosity will retard engine warmup has no basis.

But the second one is what I noted above. We aren’t measuring engine temperature anyway, it is coolant.
 
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What? You’re doing quite a dance here around which oil heats up faster in operation. It is always a higher viscosity oil unless physics has suddenly taken a vacation. So your statement above that a higher viscosity will retard engine warmup has no basis.

But the second one is what I noted above. We aren’t measuring engine temperature anyway, it is coolant.
I did not say a thicker oil would retard the engine warm-up. I did say a thicker oil would be thicker than a thinner oil at any point during the warm-up.
 
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I did not say a thicker oil would retard the engine warm-up. I did say a thicker oil would be thicker than a thinner oil at any point during the warm-up.
Really? What did this mean in the context of his engine not warming up quickly?

Use the Widman operational viscosity calculator. 0W-40 will be thicker than a 5W-30 for most temperatures; so, it will make the problem worse.
 
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Really? What did this mean in the context of his engine not warming up quickly?
The viscosity of the oil will not affect the warm-up much. The warm-up is mainly the result of the heat produced by the fuel combustion, not the heat produced by the oil friction.

The OP is experiencing poor revving due to high oil viscosity and that's why I referred him to the Widman operational-viscosity calculator. You can't make the driving operational oil viscosity lower by using an oil with a higher laboratory operational oil viscosity. That's completely illogical. The OP is right in that he needs an oil with a lower operational viscosity, and the Widman operational-viscosity calculator will be his best friend in this matter, as the 0W rating does not correspond to the cold operational viscosity but only the cold-starting and cold-pumping viscosities.
 
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The viscosity of the oil will not affect the warm-up much. The warm-up is mainly the result of the heat produced by the fuel combustion, not the heat produced by the oil friction.

The OP is experiencing poor revving due to high oil viscosity and that's why I referred him to the Widman operational-viscosity calculator. You can't make the driving operational oil viscosity lower by using an oil with a higher laboratory operational oil viscosity. That's completely illogical. The OP is right in that he needs an oil with a lower operational viscosity, and the Widman operational-viscosity calculator will be his best friend in this matter, as the 0W rating does not correspond to the cold operational viscosity but only the cold-starting and cold-pumping viscosities.
No you are wrong about the oil temperature. It is not primarily heated by the combustion but instead by shear. It is directly related to RPM.

He’s not experiencing “poor revving” he’s experiencing a warmup idle that remains high for too long. The oil viscosity is irrelevant here since the engine speed is controlled by the ECU. If what he says is true (staying too high for too long) then it’s either a bad input to the ECU, a stuck thermostat or some problem with the idle control system.

The rest of your story about cold cranking and pumpability is accurate but unrelated to the problem the OP has stated.
 
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No you are wrong about the oil temperature. It is not primarily heated by the combustion but instead by shear. It is directly related to RPM.

He’s not experiencing “poor revving” he’s experiencing a warmup idle that remains high for too long. The oil viscosity is irrelevant here since that engine speed is controlled by the ECU. If what he says is true (too long) then it’s either a bad input to the ECU, a stuck thermostat or some problem with the idle control system.

The rest of your story about cold cranking and pumpability is accurate but unrelated to the problem the OP is stating.
If OP's concern is the following, it has nothing to do with the oil, and no, it is illogical to use a thicker or thinner oil in the winter to try to remedy it.


What I was saying earlier was that it is completely illogical to expect a thicker oil to run thinner than a thinner oil. It goes against the laws of physics. If that were the case, a thicker oil would run thinner than a thinner oil in the bearings and provide a thinner oil film or smaller minimum oil-film thickness (MOFT) than a thinner oil would provide because it runs hotter. That goes against the bearing theory, models, and experiments. Moreover, through pure logic without knowing anything about lubrication, if a thick oil is expect to run thinner than a thin oil because the former gets hotter, then the thick oil becomes the thin oil and the thin oil becomes the thick oil, contradicting the statement. ;)
 
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Completely unrelated to the topic of prolonged fast idle. Moreover, the way you’ve worded it it makes it so convoluted that it makes no sense.

I do know how physics works.
 

wlk

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Nothing wrong w the PUP 5w30 you are currently running or M1 0w40, either one will be fine. And definitely do the 100k valve adjustment before you burn one.
 

Bmsluite

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Nothing wrong w the PUP 5w30 you are currently running or M1 0w40, either one will be fine. And definitely do the 100k valve adjustment before you burn one.
I will look into the valve adjustment. I'll do the VTC actuator at the same time. Thanks
 
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If short tripped, cold weather (Chicago) and OEM calls for 0w20 for this engine I'd use that. M1 0w20 EP HM is a good choice (for your 100k engine). Why would you want a higher grade here in your situation? These Honda engines are bullet proof if you maintain it reasonably.
I have used 5w30 in a J35 engine (Odyssey) and it definitely ran heavier with more vibrations than a 0w20 at anything colder than 40F.
 
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If short tripped, cold weather (Chicago) and OEM calle for 0w20 I'd use that. M1 0w20 EP HM is a good choice (for your 100k engine). Why would you want a higher grade here in your situation?
I have used 5w30 in a J35 engine (Odyssey) and it definitely ran heavier with more vibrations than a 0w20 at anything colder than 40F.
Vibrations you say? Increased MOFT dampens such things not causes them.
 
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