Can you increase idle RPM in Engine adaptation on a VW GTI MK7 with EA888 gen 3 engine?

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RGH0

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Like using the 10W-60 oil, a larger pan with additional cooling fins will help but it is compensating for a problem with a worn / faulty pump or worn engine bearings. Does you engine have an oil cooler? if so maybe you have a problem with that with inadequate coolant flow through it or high coolant temperatures due to some other issue in the coolant system, causing higher than design oil temperatures. 112C is on the high side
 
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Like using the 10W-60 oil, a larger pan with additional cooling fins will help but it is compensating for a problem with a worn / faulty pump or worn engine bearings. Does you engine have an oil cooler? if so maybe you have a problem with that with inadequate coolant flow through it or high coolant temperatures due to some other issue in the coolant system, causing higher than design oil temperatures. 112C is on the high side
Thanks for the expert opinion.

2015 GTI does have stock oil cooler. During test drive on city roads, speed about 40 to 50 miles/hour, I did turn on AC during driving, it is not hot, I just wanted to have higher idle RPM than 750 /m which I have already increased to using VCDS. I agree with you 112c appears too high for slow city road speed. 100c operating temp should be ideal in that situation. As shown, engine coolant temp is lower than oil temp or about the same. The seemingly higher oil temp around 112c on local roads and cool California winter climate may be indicative to a problem, I will check that.

Thanks again.
 
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2015 GTI does have stock oil cooler.
That's an oil-to-water cooler though, right? If so, it can't possibly make the oil cooler than the water -- and in fact it helps warm the oil during engine warm up, when typically the coolant (water/glycol) warms up faster than the oil.

While I agree that 100°C is ideal, 112°C isn't is not by any means excessively hot, and in the end, I concur with @RGH0 -- you're trying to mask a mechanical problem, either with the oil pump or bearings.

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Normal idle speed for most vw and audi engines is 800rpm just a fyi. That being said doing things half ass is just that half ass. So now your going to trade this pile into a dealership? or are you going to sell it privately so it can empty someone else's bank account. Note in most states not disclosing major mechanical issues like this leaves you open to a lawsuit should the engine fail, suddenly stop and or potentially cause an accident because of this issue, especially if you are trying to mask a major issue within the drivetrain.
 
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geyungjen

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That's an oil-to-water cooler though, right? If so, it can't possibly make the oil cooler than the water -- and in fact it helps warm the oil during engine warm up, when typically the coolant (water/glycol) warms up faster than the oil.

While I agree that 100°C is ideal, 112°C isn't is not by any means excessively hot, and in the end, I concur with @RGH0 -- you're trying to mask a mechanical problem, either with the oil pump or bearings.

-Uwe-
I agree Uwe. Oil can not be cooler than coolant at the cooler. But when oil temp was at 235 F, higher than coolant temp at engine, as shown on dashboard at the time, the I would assume coolant temp at the cooler would be <= than the coolant temp near engine, that is picked up by ECU to display at one of the meters on the dashboard. If the oil temp > coolant temp near Engine, by transitivity, oil temp would be > coolant temp at the cooler, then shouldn't the higher oil temp be brought down by the lower coolant temp at the oil cooler?

One variable however might make this phenomenon possible is the thicker oil (10W60), slower to heat up and slower to cool down. The coolant in the oil cooler (not designed to cool 10W60 quickly) does not cool oil down as fast as with thinner oil, i.e., VW502 (5W40) for this car, leading to oil temp continues to rise to > coolant temp at Engine, in this instance, 235 F or 112 C. However, I do not have data point to support this assertion.
 
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One variable however might make this phenomenon possible is the thicker oil (10W60), slower to heat up and slower to cool down.
Not sure about that. In general, I would expect a thicker oil to run a bit hotter just because there will be more friction / energy needed to pump it.

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Normal idle speed for most vw and audi engines is 800rpm just a fyi.
Bah, there's a good bit of variation. In most ECUs, there will be a place to see the commanded idle speed at any given moment.

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Bah, there's a good bit of variation. In most ECUs, there will be a place to see the commanded idle speed at any given moment.

-Uwe-
I agree yes, but for the most part it's around 800. I have seen some vw idle at 1000 always when ecm demands more juice because some jackass installed the WRONG alternator.
 
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In general, I would expect a thicker oil to run a bit hotter just because there will be more friction / energy needed to pump it.
That can be an explanation of why oil temp at 112c when the car is not driven in spirited manner, in a city street not on a track.
 
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I would expect the heat exchanger to be a counter flow design with the design oil outlet temperature being close to the coolant inlet temperature and for coolant inlet to come from the radiator outlet and be below the 90C nominal engine coolant temperature. I dont know where the temperature sensors are that are being reported so hard to comment but I would not expect VAG to design for above 110C oil temperature in the sump as above that even a good quality group 4 synthetic degrades rapidly.

The heat transfer of "thicker" fluids is generally greater than "thinner" fluids. Higher viscosity > high Reynolds number in heat tranfer tubes > higher boundary layer heat transfer which is generally the limiting factor. Many other influences in the detail design of heat exchangers but true as a generalisation
 
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I would not expect VAG to design for above 110C oil temperature in the sump as above that even a good quality group 4 synthetic degrades rapidly.
If I am not mistaken, the oil level sensor at the bottom of the oil sump measures both oil level and oil temperature, if so, 235F (112C) is the oil temperature at the bottom of the sump. I would think GTIs being driven on a track is a use case factored in the design of this car:


Anyway, I would need to see how to maintain the oil temp to around 100c with normal driving on local streets and expressways with AC on.
 
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