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Boost leak?!? NEED HELP!
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12-01-2008, 12:37 PM | #1 |
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Boost leak?!? NEED HELP!
hey everyone
this weekend i got my springs installed and after they were done i drove it around the block for the springs to adapt. but one thing i noticed was i wasn't boosting at 15 psi anymore(jbx) i was only peaking at 11 so i unswitched the X and i was only getting 8psi. today i decided to uninstall the jbx after i was done i drove around and now im only boosting at 5 psi..does anyone know what the problem is? im guessing my DC's are leaking...am i right? i had no CEL no errors no nothing what can be wrong? thanks |
12-01-2008, 12:56 PM | #3 |
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12-01-2008, 12:57 PM | #4 | |
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doesnt the dme cut boost when its super cold?
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12-01-2008, 01:35 PM | #5 |
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12-01-2008, 04:17 PM | #6 |
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its been under 40oF here for the past few weeks and i cant get my car past 6psi either. i am completely stock and i used to see 8psi+ sustained all the time. the only thing i can think of would be maybe my boost gauge needs to be recalibrated for cold temps? it is really bugging me, i have no clue what this could be but it just started happening.
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12-01-2008, 04:43 PM | #9 |
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thats what i was thinking also. my Mpg's have remained the same from when i had more boost so i dont think its a leak. maybe this will be a good excuse for me to get the new progman because i am pretty sure i have 29.2. also i want to let the dealer know about this boost shit before i put on my exhaust so they cant try and relate it to that.
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i'm not addicted to boost, but i sure am more fun when i'm on it.
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12-01-2008, 06:51 PM | #10 | |
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12-01-2008, 07:07 PM | #11 | |
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The reason the DME reduces boost is to provide load compensation; less variation in power from winter to summer. This is most likely the case in what you are seeing. Also, remember, the DME will limit boost until the engine is fully warmed. BTW, what springs were installed? |
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12-01-2008, 07:20 PM | #12 | |
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i got race springs |
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12-01-2008, 07:25 PM | #13 |
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12-01-2008, 07:30 PM | #14 | |
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and im guessing your right because thats what everyone else is saying...kinda sucks i like when i feel 15 psi does anyone know if the hot pills will work?( i doubt it will) but it does hurt to ask |
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12-01-2008, 07:30 PM | #15 |
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+1, that is what I was getting at earlier today. I have found that under 40 or so degrees i'm normally around 1.5 to 2psi below the boost targets. this is not a scientific study, just what I see when i'm actually paying attention.
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12-01-2008, 07:45 PM | #17 |
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The fuel demand would be significant to support 15 PSI, in sub-30 degree weather. Yes, you would have tons of power but wouldn't have traction until 3rd gear. Consider it a tire saving feature.
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12-01-2008, 07:48 PM | #18 |
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12-01-2008, 08:16 PM | #19 | |
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If I had been boosting to 17psi in that cold weather, well, I just dont know.
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12-01-2008, 08:36 PM | #20 | |
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But does the colder air need a lower boost pressure to achieve the same power output as warmer air would? Is that what you mean by load compensation? |
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12-01-2008, 08:39 PM | #21 |
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yes
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12-01-2008, 08:44 PM | #22 |
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i think it is what he means. lesser boost pressure with 30 degree ambient air temps can yield the same if not more power than hotter air temps boosting a few more psi. thanks scalbert for clearing that up, although it would be pretty sweet if i was still boosting the same pressure with this cold dry New Hampshire air!
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