I am still trying to nail down my P2885 problem and have ruled out the vacuum pump, pressure converter, vacuum tank and piping. When I attach a hand vac pump to the wastegate actuator, it does in fact close.

My path is leading me towards the two pressure sensors.

My Bavarian Technic is showing the following values:
1) Ambient Pressure ~800 hPa (~11psi)
2) Suction Pipe Pressure 1/ Charge Pipe Pressure 1 ~400hPa (~5psi)
3) Suction Pressure ~796hPa
4) Boost Pressure ~800hPa

I believe 2 is the pressure temperature sensor P/N 13627535069, 4 is the intake MAP P/N 13627540508.

When I unplug the P&T sensor the MIL illuminates and the value jumps to 485hPa and does not vary. In fact, this value does not move under any conditions. I went for a drive and observed this value to remain at ~400hPa for the entire drive.

My question is what should these values be at idle? It would make sense for all the values to be close to each other at idle. If this is true then the P&T sensor has failed and I can move forward.

Any input is appreciated!

 

For anybody interested, replacing the Pressure/Temperature Sensor did not resolve my issue.

I'm going to recheck the EPCC, and vacuum pump. I can hear the DV blow off a little bit of boost at high RPMs only, and Bavarian Technic software confirms some small amounts of boost at high RPMs.

This leads me to conclude either A) EPCC has failed and my test was invalid, B) vacuum pump is providing vacuum to brake system but not wastegate system, C) wastegate is shot and turbo needs a rebuild/replace.

 

Whats the code translate to?

 

P2885 is a pressure deviation - plausibility error. Essentially the engine is not sensing the pressure it is expecting. This leads down a rather strange rabbit hole of possible issues such as charge system leak, DV valve failure, EPCC failure, vacuum pump or ancillary vacuum systems failure (hoses, vacuum tank etc), wastegate failure, sensor malfunction.

PIA for short

 

Did you check map and the boost pressure sensor on the intake cold side tube? Those run plausibility checks.

 

Bavarian Technic showed the MAP sensor to be functioning properly, as the values are 'not pegged high or low' and are trending with engine speed/load as I would expect pressures in those locations to react. I replaced the hard pipe Pressure/Temperature sensor thinking its constant pressure value of 400hPa was erroneous, yet the brand new OEM sensor is displaying the same values (which left me head scratching).

What has be really buggered is that 400hPa reading. I went for a drive and watched the laptop screen (I know, not safe, but I was in a parking lot) and it doesn't budge! All other pressure sensors are reacting as expected. However when I am in third gear and the engine speed exceeds 4000rpm, when I shift I do hear a small amount of boost being blown off. Like a dog fart. Small little pssh. Aww its so cute.

This is leading me to think that possibly the vacuum control valve (EPCC) is failing. Autozone had a vacuum gauge I borrowed but they didn't have any adapters for smaller apertures, as such I couldn't test the vacuum nipple on the vacuum pump which is for the wastegate control system. I could however test the vacuum line for the brake system which is driven off of the same pump. The brake vacuum line is performing wonderfully! And clearly I can brake just fine.

Unless the two vacuum connections on the vacuum pump are somehow separate, I do not see how one vacuum connection would be functioning as expected and the other not. I'm going to call around to other auto parts shops to see if they have a vacuum gauge with adapters so I can truly test the wastegate vacuum source. I'd hate to spend the money for a new vacuum pump if it is not the source of my problems.

Long winded, I apologize.

 

Not at all , detail is good. The brake vacuum will always read good as the vacuum pump supplies it. There is an electronic solenoid which feeds vacuum to the wastegate(mini wastegate runs off of vacuum not pressure). You could check there, also check the bpv valve, if there is a tear in the diaphram it will leak pressure at the compressor(internal leak).

 

Indeed, it took me a while to realize the MINI's wastegate works counter to other vehicles. When no vacuum is supplied, the wastegate is open bypassing the turbine which is why I'm suspecting the vacuum system. When the engine speed is great enough the turbine will spin a little, generating a small amount of boost which is why I am hearing a wee bit of blow off only at high RPMs.

I'm hoping it is the EPCC (wastegate vacuum controller) however it receives vacuum from the vacuum pump, which is why I was checking the vacuum pump for starters. So you say the vacuum pump will always check out okay at the brake nipple, but the smaller nipple beneath where the wastegate vacuum source is, is NOT driven by the vacuum pump?

Also, what is the PBV valve? I have not heard of that one, yet. If you're referring to the Diverter Valve (DV), the first thing I already replaced was the stock DV with the WMW as the stock DV did have a small tear in the boot diaphram. Sadly that did not solve my problem.

 

BPV bypass valve, typo. So how much boost are you generating at WOT? To find the wastegate source trace it back to the electronic solenoid. It is driven by the pump if im not mistaken but the line will go to an electronic solinoid which will then branch off to the vacuum lines under the intake mani somewhere. I cant remember the exact line though. There is an actual vacuum tank which it leads to i beileve if i remember right.

 

Since I was driving and watching a laptop screen, I do not have an exact reading. Ambient pressure is ~800 hPa and the boost sensor was showing ~950hPa (~2psi boost).

Wastegate vacuum system:

Wastegate vacuum tube connected to output of Pressure Converter solenoid valve.
Pressure Converter solenoid valve connects to vacuum tank beneath intake manifold.
Vacuum tank connects to small nipple on lower front side of vacuum pump.

I've been toying with the idea of connecting a T into the brake vacuum line and tying the wastegate system to this known good vacuum line...

 

HMmmmm. How long after you clear the codes will the presented code return?

 

The car still drives without full boost even after I clear the code, then the code reappears.

 

Well I reached my wit's end at buying new parts HOPING they would work and took my MINI into a local import auto repair shop. A full day later they called, "we cannot work on your car because it has been modified." What modification? Oh, the cold air intake which I've had on the car since day 1. Yup. "That very well could be your problem as the ECU is designed to detect the recirculated air, and on the charge pipe there is a secondary hose which is capped." He's talking about the noise maker delete which came with the Alta CAI. What a boffin.

So, anybody know of a good MINI shop in Colorado Springs which will deal with a car that has a friggin CAI and won't **** a brick over it?