[v1nc86]

Hi there! I'm running JB4 and BMS intakes for about 18 months. I've installed a CP-E charge pipe with stock DVs about a month ago. Since a week or two, sometimes the car runs fine, but sometimes it runs at a boost level lower than stock boost. For example, I go WOT 2nd-3rd gears full boost (~13 psi on map 1), but second time I go WOT 2nd-3rd gears it takes a while to spool up and I hit maybe 5 psi... Let's say I park the car, and start it back when cold (few hours later), I get the same issue (full boost on 1st WOT and low boost on 2nd WOT). I have connected my laptop and I don't have any code. Two weeks ago, I've tried to install a VRSF 5 inches intercooler, but was not able to do it alone, so I've installed back the OEM intercooler (with new t-clamps, because remember that the I had to cut the OEM one-use clamps).
This morning, I've verified each and every bolts/clamps/hoses on the BMS intakes and the CP-E charge pipe (as well as the C-clip connection from CP to TB). Everything is fine but still getting the same boost issue. I assume the "partial" boost leak is coming from the intercooler clamps/hoses (last thing I've installed on my car), but don't wanna check today because I'll get it installed by someone on Saturday.
My question is, I don't understand how this could happen? I mean, if there is a boost leak, there should "always" be a boost leak, right? Maybe the heat create an intermittent boost leak? I've no idea...
Thanks in advance for your help!


Update:
3rd Gear Pull, Map 5, 91 octane
Datazap: http://datazap.me/u/v1nc86/intermitt...g=0&data=1-2-4

[holmes011]

Sounds kinda similar to my issue. I'm noticing a lot of people with this brief loss of power issues during WOT seem to all have bms dci's (I'm assuming you have that because you kept saying intakes). I'm starting to become cynical lol

[gigabyte]

i had a similar issue, i fixed it by replacing all of my vacuum hoses.

[v1nc86]

Originally Posted by holmes011

Sounds kinda similar to my issue. I'm noticing a lot of people with this brief loss of power issues during WOT seem to all have bms dci's (I'm assuming you have that because you kept saying intakes). I'm starting to become cynical lol

Yes, by "intakes" I mean "DCI"
To be honest, I would be surprised if my boost issue is coming from the BMS DCI. It's not a brief loss of power... I get full boost when 1st WOT, but then very low boost and it takes forewer to spool up, until I park and car and take it back a few hours later (when "cold").

[holmes011]

Lol I'm not saying the dci has anything to do with it it's just something I've noticed while trying to research the problem

[holmes011]

Also didn't realize it wasn't brief. Good luck finding the problem. Any issues shifting( if you have AT)

[v1nc86]

Originally Posted by holmes011

Lol I'm not saying the dci has anything to do with it it's just something I've noticed while trying to research the problem

Ah, ok.

Originally Posted by holmes011

Also didn't realize it wasn't brief. Good luck finding the problem. Any issues shifting( if you have AT)

I have AT but no issue at all.

[Tiago@VRSF]

Your OEM DV's could be leaking, they fail pretty often above stock boost levels.

[v1nc86]

Originally Posted by Tiago@VRSF

Your OEM DV's could be leaking, they fail pretty often above stock boost levels.

How to verify if the stock DV's died?

[Tiago@VRSF]

A boost leak test would be a great start.

[v1nc86]

Originally Posted by Tiago@VRSF

A boost leak test would be a great start.

I might do this: http://www.e90post.com/forums/showthread.php?t=193077

[v1nc86]

Fixed. The C-clip of the intercooler hot side coupler was not pushed all the way down. Anyway, a friend mechanic did help me and we did install the VRSF 5 inches intercooler, took less than 2 hours including the little test drive