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

   #21  

EuroX

Professional User
Professional VCDS User
Joined
Jun 28, 2014
Messages
4,577
Reaction score
3,040
Location
Northern NJ USA
VCDS Serial number
C?ID=208579
Best way would probably be to shim the relief valve in the oil pump. That should give it a good bump in pressure sometimes good enough for 1bar or more of additional pressure. This has been done in many race engines where oil pressure is needed.
 
   #23  

geyungjen

Verified VCDS User
Verified
Joined
Jan 9, 2025
Messages
32
Reaction score
9
Location
Fremont, CA, USA
VCDS Serial number
C?ID=606828
Best way would probably be to shim the relief valve in the oil pump. That should give it a good bump in pressure sometimes good enough for 1bar or more of additional pressure. This has been done in many race engines where oil pressure is needed.
Yes, I have this on agenda when I have the time to remove the oil pump:

Screen+Shot+2025-01-14+at+3.21.10+PM.jpg
 
   #26  

RGH0

Verified VCDS User
Verified
Joined
Mar 14, 2021
Messages
575
Reaction score
452
Location
Australia
VCDS Serial number
C?ID=433612
At idle the relief valve will be fully closed so shimming the spring does nothing. This only increases the pressure at which the valve opens which only occurs at higher RPM. It is done on race engines to increase oil flow at high engine speeds for better bearing cooling

If you have excessive bearing wear then oil pressure measured will be lower especially when your engine oil is hot but it also could be due to oil pump wear or a failed / jamming relieve valve

A new oil pump or if you can source a high volume oil pump this may correct the low idle pressure issue.

Going to a 10W / 60 full synthetic group 4 and 5 base oil lubricant will also help. These are typical sold as competition oils as they are designed to run at high temperatures with less viscosity loss.

Long term it probably going to need an engine replacement or rebuild depending on the extent of the bearing damage
 
  • Like
Reactions: Uwe
   #27  

geyungjen

Verified VCDS User
Verified
Joined
Jan 9, 2025
Messages
32
Reaction score
9
Location
Fremont, CA, USA
VCDS Serial number
C?ID=606828
"If you have excessive bearing wear then oil pressure measured will be lower especially when your engine oil is hot but it also could be due to oil pump wear or a failed / jamming relieve valve

A new oil pump or if you can source a high volume oil pump this may correct the low idle pressure issue.

Going to a 10W / 60 full synthetic group 4 and 5 base oil lubricant will also help. These are typical sold as competition oils as they are designed to run at high temperatures with less viscosity loss."

Good point. I will start with: (because that is easier to do)

Going to a 10W / 60 full synthetic group 4 and 5 base oil lubricant will also help. These are typical sold as competition oils as they are designed to run at high temperatures with less viscosity loss.
 
   #30  

geyungjen

Verified VCDS User
Verified
Joined
Jan 9, 2025
Messages
32
Reaction score
9
Location
Fremont, CA, USA
VCDS Serial number
C?ID=606828
At idle the relief valve will be fully closed so shimming the spring does nothing. This only increases the pressure at which the valve opens which only occurs at higher RPM. It is done on race engines to increase oil flow at high engine speeds for better bearing cooling

If you have excessive bearing wear then oil pressure measured will be lower especially when your engine oil is hot but it also could be due to oil pump wear or a failed / jamming relieve valve

A new oil pump or if you can source a high volume oil pump this may correct the low idle pressure issue.

Going to a 10W / 60 full synthetic group 4 and 5 base oil lubricant will also help. These are typical sold as competition oils as they are designed to run at high temperatures with less viscosity loss.

Long term it probably going to need an engine replacement or rebuild depending on the extent of the bearing damage
Hi RGH0,
Thanks for mentioning "10W / 60 full synthetic group 4 and 5 base oil lubricant", I Googled "Group 5" means "ester based", one of them is Motul 300V LE MANS 10W-60 Motor Oil, ester based.


I checked its viscosity at 100 degree is 23.6mm^2/s

Then I look at other Motul full synthetic 10w60 oils, all of them, viscosity at 100 degree are 23.6mm^2/s, those are cheaper, not ester based.

Does that data point "100 degree is 23.6mm^2/s" indicate all Motul 10W60 oils will have the same amount of viscosity loss at 100 degree C, (Group 5, ester based) or not?

Thanks again
 
   #31  

davisev5225

Verified VCDS User
Verified
Joined
Oct 9, 2016
Messages
967
Reaction score
674
Location
Democratic People's Republic of Commifornia, USA
VCDS Serial number
C?ID=263265
My man, you're going way too deep into subjects that aren't likely to solve your issue. You have a low pressure indication not because you're using the wrong oil, but because you have either a mechanical or electronic issue in your engine.

Mechanical: oil pump bypass stuck open or pump is worn out
Electronic: oil pressure switch(es) aren't properly registering the actual pressure

Stick with the pump diagnosis, don't go off in the weeds trying to learn everything there is to know about high viscosity racing oils. There's actually other reasons not to use them anyway, such as insufficient flow through tiny oil passages in the heads. Pressure isn't everything, volumetric flow is actually more important in your engine's oiling system. Too high a viscosity in an engine that wasn't designed (or modified...) for it is actually a bad thing.
 
   #32  

RGH0

Verified VCDS User
Verified
Joined
Mar 14, 2021
Messages
575
Reaction score
452
Location
Australia
VCDS Serial number
C?ID=433612
The specification data is for new oil and all 60 spec oil will be similar when new. However the cheaper oils loose their hot viscosity much faster in use due to shearing of the polyethylene additives used to increase their hot viscosity.

As for issues with higher viscosity oil in the small oil passages, it is a much stated problem but little evidence to support it. If real this would only be a problem at low temperatures as all oils low temp viscosity are much higher than at normal operating temperatures. Small passages are much more likely to be fouled with sludge and varnish / gum from cheap oil deterioration.

In the end, as has been said, you have a mechanical or electrical problem. Higher viscosity oil may enable you to carry on for sometime but in the end you will need to solve the base problem
 
   #33  

geyungjen

Verified VCDS User
Verified
Joined
Jan 9, 2025
Messages
32
Reaction score
9
Location
Fremont, CA, USA
VCDS Serial number
C?ID=606828
The specification data is for new oil and all 60 spec oil will be similar when new. However the cheaper oils loose their hot viscosity much faster in use due to shearing of the polyethylene additives used to increase their hot viscosity.

As for issues with higher viscosity oil in the small oil passages, it is a much stated problem but little evidence to support it. If real this would only be a problem at low temperatures as all oils low temp viscosity are much higher than at normal operating temperatures. Small passages are much more likely to be fouled with sludge and varnish / gum from cheap oil deterioration.

In the end, as has been said, you have a mechanical or electrical problem. Higher viscosity oil may enable you to carry on for sometime but in the end you will need to solve the base problem
Thanks for sharing the knowledge, much appreciated.
 
   #34  

geyungjen

Verified VCDS User
Verified
Joined
Jan 9, 2025
Messages
32
Reaction score
9
Location
Fremont, CA, USA
VCDS Serial number
C?ID=606828
Yes and no. Your ECU does have an Adaptation Channel for it:

IDE00259-ENG104054 -- Idle RPM correction - Idle Speed Offset

However, I'm near certain you won't be able to change it. It probably requires a Security Access code that not generic like it is on older TDIs and isn't known (at least to me).

-Uwe-
Now, I have answers to my own questions:

1. Can you increase idle RPM in Engine adaptation on a VW GTI MK7 with EA888 gen 3 engine? Yes
2. "Unlike TDIs, most Gasoline engine controllers after (roughly) model year 2005 will not allow modifications to the idle speed.", it it true? This statement is not true with VW MK7 with EA888 Gen 3 (Gas engine, non TDI).

Here are steps what I have taken:

1. Pop up the hood.
2. Connect my standalone OBD2 scanner, start the car engine running (idle of course).
3. Using the standalone OBD2 scanner device to scan and clear engine module fault code if there is any.
4. Stop and then restart engine after clearing the fault, plug in VCDS connector.
5. Launch VCDS app, Application->Controller Channels Map, select Whole Vehicle, Output to Raw Hex, Check Adaptations option, Then click Go, wait until done. This is for restoring to previous state in case adaptation goes wrong.
6. Back out all the way to the main menu, click "Select"->01 Engine->Security Access, enter 27971, the code was accepted. Note, Before try 27971, I entered 20103, which was refused. Despite warning says "...allow only one access attempt... wait 10 minutes...", I did not wait 10 minutes, immediately enter 27971, which was accepted.
7. Then back to menu, select Adaptations->Idle Speed Adjustment, default is 0 RPM/min, I set to 50 RPM/min, then click do it. The new value 50 was accepted.

IMG_2487.JPG


Exit VCDS app, re-enter VCDS to Adaptations, the stored value and new value shown are 50 /Min, the change appears to be persistent.

I did attempt to change from 50 to 100 following the same process, it will not change to 100, stay with 50, which indicates only allow delta increase of maximum 50 rpm/min from defaut delta idle rpm of 0 /min (stored value). The logic appears ignoring any RPM increase if stored value + new value > 50 / min, clicking do it will do nothing.

Thanks for all inputs, as a new bee with VCDS, I enjoy this forum discussion.
 
Last edited:
   #35  

Uwe

Benevolent Dictator
Administrator
Joined
Jan 29, 2014
Messages
53,773
Reaction score
36,343
Location
USA
VCDS Serial number
HC100001
Here are steps what I have taken:
Given what you've found, I suspect most of those steps are superfluous.
- Clearing faults in 01-Engine is probably a good idea.
- Security Access with the relevant code, which in this case seems to be 27971.
- Change the Adaptation Channel within the allowable limits.

Those limits do vary from one engine/ECU to another. Back in the old MK3 VR6 days, the I believe the limit was +/- 40 RPM. I've heard that the Eurovan's 24V VR6 will accept much larger changes, but I've never tried that.

How about trying the abbreviated procedure and changing things by 10 RPM at a time? Drop to from 50 to 40 first to see if the procedure works. Then try 60, 70, and so on, to see where the actual limit for your particular engine/ECU actually is?

-Uwe-
 
   #36  

AINils

VCDS Distributor
VCDS Distributor
Joined
Apr 3, 2020
Messages
1,314
Reaction score
1,207
Location
Germany (AIB)
VCDS Serial number
C?ID=56975
Are you also to lower that value again after you fix your issue?
Won't try that on our cars as the engine is working fine with stock value ;-) But just out for interest
 
   #37  

Dr Sheldon

Verified VCDS User
Verified
Joined
Dec 5, 2014
Messages
3,377
Reaction score
948
Location
Windsor UK
VCDS Serial number
C?ID=334979
Are you also to lower that value again after you fix your issue?
Won't try that on our cars as the engine is working fine with stock value ;-) But just out for interest

Ouch 🤕
 
   #38  

Uwe

Benevolent Dictator
Administrator
Joined
Jan 29, 2014
Messages
53,773
Reaction score
36,343
Location
USA
VCDS Serial number
HC100001
Are you also to lower that value again after you fix your issue?
I've never seen any indication on older cars that idle adjustments via Adaptation were irreversible.

-Uwe-
 
   #39  

geyungjen

Verified VCDS User
Verified
Joined
Jan 9, 2025
Messages
32
Reaction score
9
Location
Fremont, CA, USA
VCDS Serial number
C?ID=606828
Did a few more experiments:

1. Reduce idle rpm delta from stored value of 50 /min to 40 /min, not successful:

IMG_2489.JPG



Increase idle rpm delta from stored value of 50 /min to 60 /min, no error, but no change either, stay at 50 /min.

2. Attempt to activate Run In Oil Pressure, not successful with same error:

IMG_2488.JPG


The error "Conditions not met" is about ECU throw error code NRC 22, following is good illustration about the possible cause, assuming the "Request" below is a long code:
Screen+Shot+2025-01-17+at+1.25.44+PM.png


It appears ECU does not accept long code to activate Engine Run in oil pressure adaptation that the client sent to the ECU, the server.

Need to mention, I did clear Engine fault prior to the experiment, so the ECU is not in critical state, as one of the conditions need to be met.

Run in oil pressure is set by the manufacturer, i.e., VW when the car just out of assembly line, or by dealer, when a new or rebuilt engine has been installed, for the so called breaking in period of first 1000KM, while Engine is operating only in high RPM mode, i.e., oil pressure regulation control valve N428 is always in closed state. So there has to be a valid long code request to activate Run in oil pressure.

It is also probable that Activating Run In Oil Pressure requires a security access code other than 27971, same might be true to reduce stored idle RPM value.

After increase the idle RPM, which is now about 750 /min:

IMG_2492.JPG


IMG_2494.JPG



So far, the maximum idle for my VW GTI MK7 is about 750 ~ 760 rotation /min.
 
Last edited:
   #40  

geyungjen

Verified VCDS User
Verified
Joined
Jan 9, 2025
Messages
32
Reaction score
9
Location
Fremont, CA, USA
VCDS Serial number
C?ID=606828
The specification data is for new oil and all 60 spec oil will be similar when new. However the cheaper oils loose their hot viscosity much faster in use due to shearing of the polyethylene additives used to increase their hot viscosity.

As for issues with higher viscosity oil in the small oil passages, it is a much stated problem but little evidence to support it. If real this would only be a problem at low temperatures as all oils low temp viscosity are much higher than at normal operating temperatures. Small passages are much more likely to be fouled with sludge and varnish / gum from cheap oil deterioration.

In the end, as has been said, you have a mechanical or electrical problem. Higher viscosity oil may enable you to carry on for sometime but in the end you will need to solve the base problem
Hi RGH0,
I researched all the 10w60 oils and decided to use Liquimoly 10w60, good price at the well known ecommerce site:

Screen+Shot+2025-01-24+at+6.02.57+PM.png


The data point I was looking at is vicosity at 100 degree C, Liquimoly's data point appears to be one of the highest amongest different brands at 25,0 (German notation, in US, it is 25.0)

Screen+Shot+2025-01-24+at+6.04.55+PM.png



After I replaced the oil with Liquimoly 10w60 (6 Liter, the GTI needs to 6 quarts), I saw improvement in oil pressure when the car is hot:

IMG_2518.JPG




Before, even with Mobile 5W50, it would have been 0.6 bar at around 210 F (98 C), while 0.9 bar at 210 F as shown with Liquimoly 10w60.

In fact, during road test, with 10w60 oil, the oil temperature went up to 235 degree F (112 degree C, I should have configured to show temperature on dashboard in C instead of F by default) and the oil pressure went to 0.7 bar (the lowest, but better than before, 0.4 bar with VW502 oil at 5w30 or 40, note, VW502 oil is designed for this car)

I looked at the reduced oil pressure switch (The Brown one), that I have replaced wishing it were the problem, it was not. It shows 0.55 bar to 0.85 bar threshold to activate and deactivate low oil pressure warning.

IMG_2521.JPG



The specs of the oil pressure switch says that, if the oil pressure < 0.55 bar, a warning of low oil pressure will be triggered by the ECU and shown on the dashboard (with code P164D00), if there is such warning, the warning will dissapear from dashboard if later the oil pressure >= 0.85 bar.

The lowest oil pressure at 235 degree F was at 0.7 bar, above the threashold of 0.55 bar, hence there was no warning during the road test.

For now, the car is drivable, not for long distance though, do not have confidence. This is not a solution, at best it is a bandaid work around, I still plan to replace the oil pump later when I get a chance to do so. However, before attempting to replace the oil pump, not sure if the oil pump is the culprit, I may replace the stock plastic oil sump (pan) by aluminium one with cooling fins:


It holds 7 quarts of oil, and works like heatsinc to cool the oil, in an attempt to lower the oil temperature to maximum around 210 F or 100 degree C. Replacing oil sump is easier than replacing oil pump too. Let me know what do you think about aluminium oil sump with larger oil capacity that ensures oil pickup tube being fully submerged in the oil pan when the car turns and with cooling fins hoping to decrease oil temperature.

Thanks for your inputs.
 
Last edited:
Back
Top