Lack of boost

car7 · 09-23-2012, 12:03 PM

Hello, my car have been feeling slower lately. Its not really slow but not as punchy as before. I feel like it doesnt boost the same but I dont get any codes. Is that possible? Havent changed either fuel pump or turbos so maybe thats it? Any suggestions without logs? Thanks

Dmacc · 09-23-2012, 12:48 PM

Carbon build up? We need to see some logs to be able to help you out

Jeff@TopGearSolutions · 09-23-2012, 01:26 PM

Miles on vehicle?
Modifications?
Miles on plugs?

If there is actually nothing wrong with the car, you could just be used to the power.

I noticed you titled the thread "lack of boost", is there actually a low amount of boost pressure, or are you referring to the feeling of power?

car7 · 09-23-2012, 01:56 PM

Havent done carbon cleaning either, but it started feeling slower after some hard driving. Car is relatively new to me. No modification and cant log now. Modifications is coming but would like to straight this up first, so stock now. Plugs should be fine.

car7 · 09-23-2012, 02:03 PM

Well, I would say it feels like it doesnt boost the same, but at the same time you could just say it lacks of power. Really my main question is what could be wrong without throwing codes?

Wedge1967 · 09-23-2012, 02:06 PM

We have seen a lot of cars lately as they get older have boost issues due to the vacuum lines failing. Depending on the age of your car, it may be a good idea to replace the vacuum lines that go to the vacuum cans and also to the actuators. The lines have a mesh on them for heat, so it's hard to see cracks in the lines, but they go out slowly as you start dropping in vacuum. My car went from 19 psi to 8 psi in like a day. After a week of trying to figure out what the issue was, it had dropped to 4 psi and 0 at WOT. Took the dealership two hours to figure out it was just the vacuum lines. They replaced them under my CPO warranty so it only cost me a $50 deductible. I think 3 or 4 other people had the same issue within a few months. So it wouldn't hurt to check them if you feel your car is not boosting or has lost power over the course of a few weeks.

Eventually it will through a low boost code, but not until the vacuum lines fail completely.

ihc95 · 09-23-2012, 02:56 PM

If you're sure it's a boost leak, then check vacuum lines (as mentioned above) and your charge pipe.

09-23-2012, 12:03 PM	#1
car7 New Member 0 Rep 18 Posts Drives: bmw Join Date: Aug 2012 Location: Europe iTrader: (0)	Lack of boost Hello, my car have been feeling slower lately. Its not really slow but not as punchy as before. I feel like it doesnt boost the same but I dont get any codes. Is that possible? Havent changed either fuel pump or turbos so maybe thats it? Any suggestions without logs? Thanks
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09-23-2012, 12:48 PM	#2
Dmacc Colonel 200 Rep 2,799 Posts Drives: 2011 BMW 1M Join Date: Mar 2010 Location: So Cal iTrader: (1)	Carbon build up? We need to see some logs to be able to help you out __________________ thanks to MGallop
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09-23-2012, 01:26 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)	Miles on vehicle? Modifications? Miles on plugs? If there is actually nothing wrong with the car, you could just be used to the power. I noticed you titled the thread "lack of boost", is there actually a low amount of boost pressure, or are you referring to the feeling of power?
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09-23-2012, 01:56 PM	#4
car7 New Member 0 Rep 18 Posts Drives: bmw Join Date: Aug 2012 Location: Europe iTrader: (0)	Havent done carbon cleaning either, but it started feeling slower after some hard driving. Car is relatively new to me. No modification and cant log now. Modifications is coming but would like to straight this up first, so stock now. Plugs should be fine.
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09-23-2012, 02:03 PM	#5
car7 New Member 0 Rep 18 Posts Drives: bmw Join Date: Aug 2012 Location: Europe iTrader: (0)	Well, I would say it feels like it doesnt boost the same, but at the same time you could just say it lacks of power. Really my main question is what could be wrong without throwing codes?
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09-23-2012, 02:06 PM	#6
Wedge1967 Banned 125 Rep 2,172 Posts Drives: '07 e92 AT Sport Montego Blue Join Date: Sep 2011 Location: Portland, OR iTrader: (3)	We have seen a lot of cars lately as they get older have boost issues due to the vacuum lines failing. Depending on the age of your car, it may be a good idea to replace the vacuum lines that go to the vacuum cans and also to the actuators. The lines have a mesh on them for heat, so it's hard to see cracks in the lines, but they go out slowly as you start dropping in vacuum. My car went from 19 psi to 8 psi in like a day. After a week of trying to figure out what the issue was, it had dropped to 4 psi and 0 at WOT. Took the dealership two hours to figure out it was just the vacuum lines. They replaced them under my CPO warranty so it only cost me a $50 deductible. I think 3 or 4 other people had the same issue within a few months. So it wouldn't hurt to check them if you feel your car is not boosting or has lost power over the course of a few weeks. Eventually it will through a low boost code, but not until the vacuum lines fail completely.
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09-23-2012, 02:56 PM	#7
ihc95 Major 145 Rep 1,314 Posts Drives: 2021 X3 M40i, 2018 Mustang GT Join Date: Jul 2011 Location: NJ iTrader: (1) Garage List 2007 BMW 335i Coupe [0.00]	If you're sure it's a boost leak, then check vacuum lines (as mentioned above) and your charge pipe.
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