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David Cline I have been troubleshooting a low power/limp mode in my 06 BRM for going on a few weeks now, and I have yet to find a conclusive problem. Here is the link to my first posting http://www.myturbodiesel.com/threads/brm-loss-of-power-minor-lag-and-boost-at-idle.30160/ What I have tested so far. I have borrowed a friends working N75 valve and did not fix the problem. Driving the vehicle with my VCDS these are the findings so far: WOT high RPM: MAF actual, the most I can get is 700(I can't remember the units) Myturbodiesel FAQ says that BRMs should read 8-900+. No codes displayed. Did the dumb thing of buying the only MAF that I could find locally from Autozone, change the sensor, clear the data logs/DTCs, drive the car. No noticiable change. live data now only reads mid 600s. After a few restarts I get a CEL for P101 in block 00257 MAF sensor implausible signal. So I dont think my OEM MAF is bad and this piece of junk is getting returned as faulty. What I have noticed, and that leads me to believe I have a bad MAP sensor, is when I check the measuring blocks. Atmospheric (baro) pressure is 999.8, and WOT MAP actual reads 2200-2300 and calculated reads that same, or within 10-20. Doing the math, 2300-999.8=1300.2 mbar=18.85PSI. Well my boost gauge is displaying 12-13 psi=896.3+999.8=1896.1 mbar So either my boost gauge is off, or my MAP sensor is not working and that car thinks its running fine. I have read through the forum FAQ on low power/Limp mode issues, and I dont see the MAP testing procedure or cause, so am I testing this correctly? or am I running down another dead end road? #1 · Sep 30, 2016 (Edited) I have been troubleshooting a low power/limp mode in my 06 BRM for going on a few weeks now, and I have yet to find a conclusive problem. Here is the link to my first posting http://www.myturbodiesel.com/threads/brm-loss-of-power-minor-lag-and-boost-at-idle.30160/ What I have tested so far. I have borrowed a friends working N75 valve and did not fix the problem. Driving the vehicle with my VCDS these are the findings so far: WOT high RPM: MAF actual, the most I can get is 700(I can't remember the units) Myturbodiesel FAQ says that BRMs should read 8-900+. No codes displayed. Did the dumb thing of buying the only MAF that I could find locally from Autozone, change the sensor, clear the data logs/DTCs, drive the car. No noticiable change. live data now only reads mid 600s. After a few restarts I get a CEL for P101 in block 00257 MAF sensor implausible signal. So I dont think my OEM MAF is bad and this piece of junk is getting returned as faulty. What I have noticed, and that leads me to believe I have a bad MAP sensor, is when I check the measuring blocks. Atmospheric (baro) pressure is 999.8, and WOT MAP actual reads 2200-2300 and calculated reads that same, or within 10-20. Doing the math, 2300-999.8=1300.2 mbar=18.85PSI. Well my boost gauge is displaying 12-13 psi=896.3+999.8=1896.1 mbar So either my boost gauge is off, or my MAP sensor is not working and that car thinks its running fine. I have read through the forum FAQ on low power/Limp mode issues, and I dont see the MAP testing procedure or cause, so am I testing this correctly? or am I running down another dead end road? See less See more Sort by Oldest first Oldest first Newest first Most reactions #2 · Oct 6, 2016 Worth a shot if it's showing higher than actual boost. But also consider where the sensor is vs. where your boost gauge is. There can be pressure drops along the intake pathway. #3 · Oct 6, 2016 New OEM MAP sensor arrived this evening, I will post results tom. The boost gauge line is tapped in the charge tube between the anti shutter valve, and the IC where the map sensor is located, so they are 6" apart. It has always been accurate for the 2 years I have had it installed. If this doesn't solve my problem it's on to testing the VNT actuator, then sending ECM out for a sympathy reflash if some way possible the tune was corrupted? #6 · May 16, 2021

David Cline said: New OEM MAP sensor arrived this evening, I will post results tom. The boost gauge line is tapped in the charge tube between the anti shutter valve, and the IC where the map sensor is located, so they are 6" apart. It has always been accurate for the 2 years I have had it installed. If this doesn't solve my problem it's on to testing the VNT actuator, then sending ECM out for a sympathy reflash if some way possible the tune was corrupted? Click to expand...

Did the new OEM MAP sensor fix this problem? Show more replies 0 Reply #4 · Oct 11, 2016 Pretty unlikely the flash was corrupted. Test the VNT actuator with it disconnected at the lever, shoudl move with light fingertip pressure. #5 · May 16, 2021 Yeah I know... this thread is ancient. But it appears unresolved and I have literally this exact same problem. I have a 2006 Jetta TDI [BRM] with a Malone stage 2 tune (dynamic EGR) and it is down on power. It is also giving me an engine code of P0237 and more recently P0121 (unplugged throttle body). I am getting the following in measuring block 011: RPM: ~819 /min Specified: 1010-1020 mbar Actual: 2193 mbar Duty: 6.7 % Actual boost pressure is not changing with RPMs, even though requested is. I have checked the N75 and turbo actuator with VCDS and a vacuum pump, they're fine. Any help would be very appreciated. Insert Quotes Post Reply

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