New Boost Problem
Thread Starter
Audiworld Junior Member
Joined: May 2006
Posts: 355
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From: Cincinnati, Ohio
New Boost Problem
Taking a nice easy cruise home from work last week,I noticed (in 5th gear) my boost gauge was burried at 25 psi. I played around with my driving but it never went that high again. The next following days I noticed the same problem. As time goes on it has gotten worse and worse- which brings me to today... When I give it full gas, the gauge is burried past 25 psi, the engine starts to studder and bog, and the check engine light even starts to flash. I've noticed this to be a problem in high gears (4,5,6) more so then low gears (1st, 2, 3) but it's gotten to the point where I can't fully accelerating w/o fear of burning out the turbo, or valves- or whatever decides to give first. I am using the ModShack BM- and have tuned it down to 0 turnes (with no change in output). I'm also using the Forge Diverter Valve (relo kit) with the yellow spring now. I have other mods, but these seem to be the only ones that could be causing the problems. Any ideas on what could be wrong? N75 gone bad? Did I miss a hose that may have popped off? What are your ideas?
Thanks!
Joe
Thanks!
Joe
AudiWorld Super User
Joined: Nov 2004
Posts: 10,902
Likes: 3
Are you chipped? I think there is also some issue with faulty N75 valves, or leaks in hoses around
the N75 that can cause this. The N75 opens the wastegate, to dump the pressure. If it doesn't open, you get overpressure. Should be some old posts on this that you can search for.
Thread Starter
Audiworld Junior Member
Joined: May 2006
Posts: 355
Likes: 0
From: Cincinnati, Ohio
Yes, I am chipped
N75 was my first thought... and I did look at all the hoses to make sure there weren't any leaks- everything appeared to check out ok. I normally go to old posts to check for problems, but with the specific nature of my problem, I figured it'd be easier just to ask using my own words to describe the problem.
Any recomendations for new N75's?
Any recomendations for new N75's?
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AudiWorld Uber User
Joined: Dec 2000
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Your N75 is probably fine...>>
When you unplug it it defaults to No boost (routes to the intake). What is most likely bad is the line from the N75 to the wastegate as Mike said. There have been several failures of this line reported.. Leak in hose, Wastegate doesn't open, car over boosts.
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New Member
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Easiest way to see if it is BM related is to unplug it &
try connecting the N75 as original....
The same has just happened to me .. I replaced my N75 with a new one & re-routed the hoses to leave the boost machine unpluged.... now I see the 25 psi mark sustained all the time .. but in my case it is just fine like that
....
My overboosting went up to 30psi !!!! .... tomorrow I will plug the BM back in & see if the problem was related to my prior N75 or to the BM ...
Some other times, like people have already said... hoses that go to the N75 tend to break & fail....not making the wastegate to open... double chec all the hoses that plug into the N75, after trying with the BM unplugged ...
Cheers & good luck !!!
Robo
The same has just happened to me .. I replaced my N75 with a new one & re-routed the hoses to leave the boost machine unpluged.... now I see the 25 psi mark sustained all the time .. but in my case it is just fine like that
....My overboosting went up to 30psi !!!! .... tomorrow I will plug the BM back in & see if the problem was related to my prior N75 or to the BM ...
Some other times, like people have already said... hoses that go to the N75 tend to break & fail....not making the wastegate to open... double chec all the hoses that plug into the N75, after trying with the BM unplugged ...
Cheers & good luck !!!
Robo