evocivicmarc88

iTrader: (10)

Brief background on the car: I purchased it used 2 months ago and was tuned with a boost solenoid, tbe and drop in filter. I since recently put the injen kit on with the intercooler piping and intake. My problem is that the boost will not hold in 4th and 5th gear, and it shifts violently all over the place. I am ruling out the fact that it is a boost leak, because when I do a pull in 1st through 3rd gear the boost holds fine.

Ive attached a video to help display my problem...
In the beginning I do a 2nd and 3rd gear pull and the boost holds fine but then I go to do a 5th gear pull and the boost gauge is all over the place yet I am flooring it the whole time.

http://www.youtube.com/watch?v=i2tcm7ymtH4

I would appreciate anyones help and advice on the subject, im wondering if just might be in the tune itself being that the car was originally tuned with a drop in filter and now I have completely changed the way air is coming into the turbo.

Thanks!

heel2toe

iTrader: (41)

It appears that its your BOV fluttering...What happens when you do a pull from 2nd to 4th? I would imagine that it pulls through the gear cleanly. Basically when you just put it in a higher gear such as 4th or 5th it is putting a great deal of load on the motor, thus causing it to work harder.

evocivicmarc88

iTrader: (10)

2nd to 4th pulls clean. Its like whenever I do a full run through the gears it pulls fine, but when im just cruising in 4th or 5th and punch it the boost does what it did at the end of the video. When it was just on the stock airbox with a drop in filter I never noticed this problem at all when looking down at the boost gauge.

BluEVOIX

iTrader: (69)

Spark plug gap might be too large?

evocivicmarc88

iTrader: (10)

I haven't touched the spark plugs at all, and when I was on the stock airbox like 2 weeks ago I never had this problem.

chaotichoax

iTrader: (149)

just a tip

never rule out a boost leak test until you do it

it's 100% worth the $10 investment in random parts to make a tester and the 30 minutes it'll take you to doit

evocivicmarc88

iTrader: (10)

But I would think if I had a boost leak, this problem would occur throughout all the gears....

evocivicmarc88

iTrader: (10)

Judging from the sound it seems like compressor surge, although im not sure how that would be possible with so few modifications on the car.

javicracer

iTrader: (82)

bov is fluttering so this is one of the problems, the other one might be tune.

hazdaddy

iTrader: (1)

i agree that the plug gap might be too large. it may not have done it with stock airbox but if you changed how much air it gets in any way, it could be the problem

evocivicmarc88

iTrader: (10)

Im going to check the spark plug gap tomorrow in my auto shop class. If they are too large, would I be able to adjust them down to a reasonable level? Or would I have to by new spark plugs? I searched and with my mods it seems like around .024 is a good size.

nonschlont

iTrader: (3)

I have the same exact isssue! Unfortuneately for me, now it does this in 3rd, starting from 2000, (which was my normal starting point for third.) Will definitely do it if I try to go WOT in higher gears at lower rpm's! From my understanding, it sounds like compressor surge. Im hoping that its from my BOV leaking. I purchased a used aps, hopefully this will cure that...

Its also my understanding that trying to go WOT in 5th or 6th @ 2500 is too early! Shouldnt really being going WOT till ~3500+ (5th, or 6th) some ppl get away w/ doing their 4th gear pulls from 2500 (which was my normal starting point), but now I surge, even get a slight surge (for a sec) if I go @ 3000... Its fkn irritataing!

from what Ive gathered, possibilities are: BOV, boost leak/'s, wastegate.

I feel I have a boost leak/'s, but did the smoke machine test @ 15psi, and nothing... Just bought a pressure tester, so, gonna fully pressurize the system w/ 25 psi, and see what I find. Im trying to narrow it down. I think appauld had a similar issue, he swapped out the wastgate, and its gone for him. I also hear some type of metallic sound (high pitch) occasionally, which could possibly be the wastegate...

I hope we can find a definite fix for this...

06mr775

iTrader: (8)

What boost solenoid are you using?

nonschlont

iTrader: (3)

GM 3-Port

evocivicmarc88

iTrader: (10)

Yeah I have the same one as well.