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View Full Version : Boost Issues - Video inside with logs to come



Believer
09-18-2013, 08:24 AM
Hello all

Let me start with a little history to set a bit of context.

My car is a 99.5 1.8t with a 007 DV, 3" HFC/DP and 2.25" after the flex pipe. I'm running Kompresd Stage 1 tune.

When I first got the tune installed, I wasn't seeing anywhere near the boost the tune is supposed to deliver. I would rarely see over 12 psi on my gauge no matter what I was doing. I performed a boost leak test and everything held solid so I thought at the time my 2.25" downpipe was causing issues and installed an 034 3" DP I got for really cheap. That didn't solve anything either.

So I took a step back and thought maybe my n75 is faulty and swapped my brother's in. Right away i saw positive changes. I was hitting the boost the tune was supposed to, spiking maybe one or two psi high and holding 17/18 right to 5k. I was extatic..

So I got curious to see how the tune responded to a pull from around 2-2.5k. This is when things got really, really wierd. I have a link to a video below that shows exactly what i experience.

https://docs.google.com/file/d/0B6bElYB_T9BFeEV3VjdCMmlQUzA/edit?usp=sharing

What I have in the video is what happens MOST times I try to do a low rpm pull at WOT. A couple of times I have experienced this: 3rd gear ~2k rpm, mash the pedal, the boost starts to build but spikes to 20+ and instantly the power just dies. The boost will creep back to 18/19 but the power just doesn't feel right. Unfortunately I have not been able to capture this on video as it is much less frequent.

To clarify - If I say am cruising in 2nd gear at around 3k rpms and mash it, I will see about 10 psi on the gauge. If i continue to hold WOT into 3rd gear my boost behaves completely normal.. Meaning my gauge pins to 17/18 psi and holds there until its supposed to.. But this ONLY happens if I am rowing through the gears.. I hope i explained that in an understandable way.

I am completely confused by what is going on and am at a loss. I have an order in for a brand new n75 valve as my brother will need his back. I tried to data log on the way to work this morning, when I took the video, but apparently i'm a little green at taking logs and need to relog on my way home, which I will post to this thread.

I am asking for any and all suggestions, thoughts and input regarding this. Thanks a lot

Believer
09-19-2013, 08:30 AM
So, this log below is not from the run where I took that video although it is from the same kind of pull; low rpm, full throttle in 2nd or 3rd gear (I can't remember which). I had to let off the throttle because someone pulled in front of me.

http://farm3.staticflickr.com/2871/9820051994_f92bc63e89_b.jpg (http://www.flickr.com/photos/27566173@N04/9820051994/)