Vacuum reading at idle....

cstmx_ryder · 05-07-2014, 03:37 PM

For those who are in the Northwest with FBO N54s, can you tell me what your vacuum reading is at idle, on a cold start?

I think mine's off, and still trying to figure out what's wrong with the car.

I don't know if geographical locations matter, but just trying to stay as consistent as possible.

TIA

CT335xi · 05-07-2014, 04:05 PM

I don't think area should play a factor just whether you have a boost leak, mines read about -11 to 12.

Jeff@TopGearSolutions · 05-07-2014, 04:30 PM

Elevation would make it vary. Humidity and temperature would only make it vary slightly but negligible otherwise.

cstmx_ryder · 05-07-2014, 05:20 PM

Quote:

Originally Posted by CT335xi

I don't think area should play a factor just whether you have a boost leak, mines read about -11 to 12.

Thanks,

My elevation is around 175' above sea level.

CT335xi · 05-07-2014, 05:44 PM

Quote:

Originally Posted by cstmx_ryder

Thanks,

My elevation is around 175' above sea level.

Sea level is always a good thing. Hope you find your issue.

cwarren · 05-07-2014, 08:57 PM

Quote:

Originally Posted by cstmx_ryder

For those who are in the Northwest with FBO N54s, can you tell me what your vacuum reading is at idle, on a cold start?

I think mine's off, and still trying to figure out what's wrong with the car.

I don't know if geographical locations matter, but just trying to stay as consistent as possible.

TIA

pretty sure mines the same buddy but i will double check and let you know

pits200 · 05-07-2014, 09:48 PM

Mine varies from 17 to 22

Allen@MOTIV · 05-07-2014, 10:04 PM

Once up to temp it should be around 20"

cstmx_ryder · 05-07-2014, 10:16 PM

I'm pretty sure mine is off, just don't know by how much....lol.

Being driving her a while now, very sensitive to changes....

TIA

pwr hungry · 05-08-2014, 02:48 PM

I'm -20 - -22 at 2xx feet above sea level at idle with stock turbos.

CT335xi · 05-08-2014, 04:58 PM

Mines reads -11-12 on a cobb ap does that sound normal ? Just asking cause I don't know if the cobb would read different then a mechanical boost gauge.I have never had a boost leak code.

C.Pop · 05-08-2014, 05:28 PM

Quote:

Originally Posted by CT335xi

Mines reads -11-12 on a cobb ap does that sound normal ? Just asking cause I don't know if the cobb would read different then a mechanical boost gauge.I have never had a boost leak code.

Looks about right. It's actually pretty high (good). Mine doesn't get that high of a vac unless I'm in gear decellerating.

http://www.convertunits.com/from/in+Hg/to/psi

CT335xi · 05-08-2014, 05:54 PM

Quote:

Originally Posted by C.Pop

Looks about right. It's actually pretty high (good). Mine doesn't get that high of a vac unless I'm in gear decellerating.

http://www.convertunits.com/from/in+Hg/to/psi

Cool thats actually my reading at idle and in gear on deceleration it probably reads another -2 to 3 in+hg, I'll have to check that next time. Thanks man

tiangco.a · 05-09-2014, 01:34 AM

Quote:

Originally Posted by CT335xi

Mines reads -11-12 on a cobb ap does that sound normal ? Just asking cause I don't know if the cobb would read different then a mechanical boost gauge.I have never had a boost leak code.

I could be wrong but I don't think you can accurately read the vacuum at idle with the cobb ap. I just tested mine today because of a bov issue and I'm -17in/hg. I'm also like 1100+M above sea level

cstmx_ryder · 05-09-2014, 02:06 PM

Ya, just checked my vacuum idle on cold start, and it definitely isn't normal, I don't think.

It's sitting @ -15 and sometimes bounces to -14 or -13.

shawntech · 05-09-2014, 02:07 PM

mine is low too, having the intake ports cleaned Monday and i'll see if it goes up... but it could be VVT affecting idle results as well

Gugs · 05-09-2014, 02:43 PM

At idle- 19-21 is normal. Use a real boost gauge not cobb. Anything less indicates a leak.

cstmx_ryder · 05-09-2014, 04:35 PM

Here's the video of my vacuum idle:

Gugs · 05-09-2014, 05:02 PM

Quote:

Originally Posted by cstmx_ryder

Here's the video of my vacuum idle:

Nice private video we dont need. 19-21 is vacuum idle

Infamy · 05-09-2014, 05:11 PM

My P3 vent gauge says 18-20 at idle

cstmx_ryder · 05-13-2014, 03:09 PM

Checked the CP, cleaned DVs, Cleaned DCI. Still no luck.

Also scanned the car with BT cable, no major fault codes related to the MSDS, engine, etc. No codes what so ever when driving (cruising or WOT).

Next is replacing vacuum lines, check for holes in the silicone elbow (between CP and FMIC), and check for holes in the DPs (RR DPs has two extra O2 sensor holes plugged up by a plug/bolt, and it has unscrewed itself and fell before).

Just a little update on how the car drives:

Throttle feels 'dead' at light to moderate acceleration, very NA-like.
Slow to build boost, but boost will hit target @ heavy acceleration, just much later in the RPMs.
Loud hissing sound when WOT @ 4th gear. Seems to be coming from the driver side (just sounds like something is leaking).
Data-log to see WG DC and things related.

Those are what's left to check, if you guys have any more ideas, please chime in.

It's still FML at this point.....

TIA

Jeff@TopGearSolutions · 05-13-2014, 03:15 PM

Loud hissing and possibly squealing noise? Sounds like a boost leak, possibly at FMIC if drivers side.

05-07-2014, 03:37 PM	#1
cstmx_ryder Colonel 164 Rep 2,875 Posts Drives: A metal box with a roundel Join Date: Jul 2007 Location: Portland, OR iTrader: (2)	Vacuum reading at idle.... For those who are in the Northwest with FBO N54s, can you tell me what your vacuum reading is at idle, on a cold start? I think mine's off, and still trying to figure out what's wrong with the car. I don't know if geographical locations matter, but just trying to stay as consistent as possible. TIA __________________ '08 AW E90 335i PROcede V5 \| BMS DCI \| RR DPs \| ETS FMIC \| FORGE DVs \| Stett CP \| Vanguard \| PSS10
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05-07-2014, 04:05 PM	#2
CT335xi Major 684 Rep 1,434 Posts Drives: 2022 x5 m50i, 2005 evo 8 Join Date: Dec 2011 Location: Newtown, Ct iTrader: (0)	I don't think area should play a factor just whether you have a boost leak, mines read about -11 to 12. __________________ 2022 x5 m50i - Dravit grey 2005 evo 8 (current) built 2.3 488/409 mustang dyno Old stable mates - 87 325i, 88 m3, 90 m3, 97 m3 4dr, 04 325xi, 91 gmc Syclone, 08 335xi, and 13 x3 35i msp 2014 x5 50i msport
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05-07-2014, 04:30 PM	#3
Jeff@TopGearSolutions 3441 Rep 79,211 Posts Drives: C6 Z06, 09 335i, 10 335xi Join Date: Dec 2008 Location: www.TopGearSolutions.com iTrader: (37)	Elevation would make it vary. Humidity and temperature would only make it vary slightly but negligible otherwise.
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05-07-2014, 09:48 PM	#7
pits200 Colonel 547 Rep 2,590 Posts Drives: 09 335i X-Drive Black Sapphire Join Date: Mar 2010 Location: Pittsburgh iTrader: (1)	Mine varies from 17 to 22
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05-07-2014, 10:04 PM	#8
Allen@MOTIV 38 Rep 634 Posts Drives: 135i Join Date: Jun 2013 Location: VA iTrader: (0)	Once up to temp it should be around 20"
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05-07-2014, 10:16 PM	#9
cstmx_ryder Colonel 164 Rep 2,875 Posts Drives: A metal box with a roundel Join Date: Jul 2007 Location: Portland, OR iTrader: (2)	I'm pretty sure mine is off, just don't know by how much....lol. Being driving her a while now, very sensitive to changes.... TIA __________________ '08 AW E90 335i PROcede V5 \| BMS DCI \| RR DPs \| ETS FMIC \| FORGE DVs \| Stett CP \| Vanguard \| PSS10
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05-08-2014, 02:48 PM	#10
pwr hungry Banned 41 Rep 1,257 Posts Drives: 335 Join Date: Mar 2013 Location: Amer'ca iTrader: (2)	I'm -20 - -22 at 2xx feet above sea level at idle with stock turbos.
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05-08-2014, 04:58 PM	#11
CT335xi Major 684 Rep 1,434 Posts Drives: 2022 x5 m50i, 2005 evo 8 Join Date: Dec 2011 Location: Newtown, Ct iTrader: (0)	Mines reads -11-12 on a cobb ap does that sound normal ? Just asking cause I don't know if the cobb would read different then a mechanical boost gauge.I have never had a boost leak code. __________________ 2022 x5 m50i - Dravit grey 2005 evo 8 (current) built 2.3 488/409 mustang dyno Old stable mates - 87 325i, 88 m3, 90 m3, 97 m3 4dr, 04 325xi, 91 gmc Syclone, 08 335xi, and 13 x3 35i msp 2014 x5 50i msport
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05-09-2014, 02:06 PM	#15
cstmx_ryder Colonel 164 Rep 2,875 Posts Drives: A metal box with a roundel Join Date: Jul 2007 Location: Portland, OR iTrader: (2)	Ya, just checked my vacuum idle on cold start, and it definitely isn't normal, I don't think. It's sitting @ -15 and sometimes bounces to -14 or -13. __________________ '08 AW E90 335i PROcede V5 \| BMS DCI \| RR DPs \| ETS FMIC \| FORGE DVs \| Stett CP \| Vanguard \| PSS10
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05-09-2014, 02:07 PM	#16
shawntech The Wolf 247 Rep 987 Posts Drives: stuff Join Date: Oct 2013 Location: Midwest iTrader: (0) Garage List [0.00] 2019 BMW M850i conv ... [0.00]	mine is low too, having the intake ports cleaned Monday and i'll see if it goes up... but it could be VVT affecting idle results as well __________________ -2019 BMW m850i convertible -2021 Dodge Charger Hellcat Redeye Widebody
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05-09-2014, 02:43 PM	#17
Gugs Banned 28 Rep 457 Posts Drives: E92 JetBlack Join Date: Jul 2012 Location: Long island iTrader: (1)	At idle- 19-21 is normal. Use a real boost gauge not cobb. Anything less indicates a leak.
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05-09-2014, 04:35 PM	#18
cstmx_ryder Colonel 164 Rep 2,875 Posts Drives: A metal box with a roundel Join Date: Jul 2007 Location: Portland, OR iTrader: (2)	Here's the video of my vacuum idle: __________________ '08 AW E90 335i PROcede V5 \| BMS DCI \| RR DPs \| ETS FMIC \| FORGE DVs \| Stett CP \| Vanguard \| PSS10
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05-09-2014, 05:11 PM	#20
Infamy underground 63 Rep 331 Posts Drives: alpine white 335 E92 Join Date: Aug 2013 Location: central Jersey iTrader: (1) Garage List 2010 BMW 335i [9.66]	My P3 vent gauge says 18-20 at idle __________________
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05-13-2014, 03:09 PM	#21
cstmx_ryder Colonel 164 Rep 2,875 Posts Drives: A metal box with a roundel Join Date: Jul 2007 Location: Portland, OR iTrader: (2)	Checked the CP, cleaned DVs, Cleaned DCI. Still no luck. Also scanned the car with BT cable, no major fault codes related to the MSDS, engine, etc. No codes what so ever when driving (cruising or WOT). Next is replacing vacuum lines, check for holes in the silicone elbow (between CP and FMIC), and check for holes in the DPs (RR DPs has two extra O2 sensor holes plugged up by a plug/bolt, and it has unscrewed itself and fell before). Just a little update on how the car drives: Throttle feels 'dead' at light to moderate acceleration, very NA-like. Slow to build boost, but boost will hit target @ heavy acceleration, just much later in the RPMs. Loud hissing sound when WOT @ 4th gear. Seems to be coming from the driver side (just sounds like something is leaking). Data-log to see WG DC and things related. Those are what's left to check, if you guys have any more ideas, please chime in. It's still FML at this point..... TIA __________________ '08 AW E90 335i PROcede V5 \| BMS DCI \| RR DPs \| ETS FMIC \| FORGE DVs \| Stett CP \| Vanguard \| PSS10
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05-13-2014, 03:15 PM	#22
Jeff@TopGearSolutions 3441 Rep 79,211 Posts Drives: C6 Z06, 09 335i, 10 335xi Join Date: Dec 2008 Location: www.TopGearSolutions.com iTrader: (37)	Loud hissing and possibly squealing noise? Sounds like a boost leak, possibly at FMIC if drivers side.
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