M3 SMG Pump Errors - interesting data

[mattman928]

I know the dreaded 38 Hydraulic Pressure error has been discussed, but I noticed some behaviors during my tests that I have not seen discussed before, and was hoping someone may have some insight.

So I was able to run some more tests today using the iCarSoft device. I noticed that when the hydraulic oil temp was normal the 60 Deg C, the pump turned on around 60 BAR and turned off at 80 BAR. I did notice that as the temperature started to rise the pump on off pressure did also. Today was a pretty cool day so during the rush hour commute the temperature got up to only about 76 Deg C. At that temp the pump came on at 70 BAR and turned off at 90BAR. I noticed yesterday during the very hot day when the oil was around 96 Deg C, the pump range went from 75 BAR to 95 Bar.

When the Pressure hit 94 BAR, the lights came on the SMG threw a Hydraulic Pressure Error.
So my question is why on earth is the pressure range shifting with the temperature (i.e. which part is failing, because the pump and accumulator seem fine). I get it that pressure and temperature are related, but since the on off pressure setting is a setpoint, the computer should be able to adjust, so I am not sure why this is happening, but it certainly explains why folks are getting errors on hot days.

[MassiveWalrus]

I used to own one of these... I threw a bunch of $$ at it before I sold it. 13 62 1 433 076 that could be your problem not sure.... Good luck.