Power loss? After intake install

[NellySTL281]

i've always had a lack of power from my gsx from the start. until the turbo kicks in, it never really moved even. but now after i installed my intake, it completely does nothing even with it floored untill about 3600 when the turbo starts boosting more. any help would be appreciated. i have no clue what the problem is. i thought maybe the o2 sensor (rough idling sometimes also) thanks

 

[DSMSpyder99]

WTF major boost leak some where. i would start spooling my T25 at 2000RPM and reach 15PSI at 2700RPM. Do a Boost Leak Test u can find a write up on vfaq.com

 

[oldman]

i've always had a lack of power from my gsx from the start. until the turbo kicks in, it never really moved even. but now after i installed my intake, it completely does nothing even with it floored untill about 3600 when the turbo starts boosting more. any help would be appreciated. i have no clue what the problem is. i thought maybe the o2 sensor (rough idling sometimes also) thanks

Majore boost leak.
Majore exhaust leak before o2.
Faulty actuator.
Dying turbo.

Just some possibilities. Good luck.

 

[Templisk]

Here's a link for testing for boost leaks.
http://www.vfaq.com/mods/ICtester.html

 

[NellySTL281]

Alright thanks for the help guys, but now i put on my exhaust and high flow cat last night (3 in cat, 2.5 in cat) and it still bogs. i took it around the block, everything checked fine. i checked for leaks in the exhaust, everything is tight. then i start it up this morning, and bam, same stuff, but now my CEL is on. any suggestions on this now? also my gas mileage is pretty bad, it idles rough, sometimes stalls and this is what led me to believe it's the o2 sensor...any input will be appreciated, thanks

 

[90CherryTSI]

check the CEL with a logger and if it bogs under WOT you have a boost leak. Have an A/F gauge? The first thing that set me off to big boost leak was that it pegged full rich during 50% throttle. Finding and fixing all the leaks fixed this. Do a test, get a logger to check the CEL and you'll be fine. Fix the problems before you continue to mod, otherwise stuff is just going to keep building. Give the car running good at each stage. You've now moved on to a whole new stage w/o fixing the problems it had before.

 

[NellySTL281]

Alright, thanks...right now im flat broke, but as soon as i make a little cash, i'll get a datalogger, and boost/af/egt gauges. thanks again for the help

 

[lazylaser]

From what I understand about 2g's, theres a second 02 sensor near the end of the exhaust and if disconnected it can throw a CEL. Maybe thats your CEL.

 

[Agent11br]

CEL may be a result of the highflow cat, the rear 02 sensor might not like it.

Your bogging and such is, my guess, your stock POS 2g bov. If you are running that or you are venting then that is your issue. I put my money on the bov. That or your turbo is shot. Check for shaft play.

 

[JiveMasterT]

do a boost leak check. thats what it sounds like to me...

or check your fuel filter. bogging and stalling? sounds like it may be a fuel delivery issue.

 

[NellySTL281]

alright, i did take out the rear o2 sensor to change my exhaust, if thats the only problem, then how do i get the cel to go off? also, i am pretty sure i am running too rich, cause it smells like tons of gas. i also heard a beep noise, but i couldnt tell where it was coming from, it was after i turned off my car (turbo timer still letting it run) and it would beep. is this because of the cel on or is it something else? thanks (sorry if these are newbie questions, i just dont know what to do)

on a side note, if i do replace my o2 sensor, which one would i want to replace, the rear one or front one (or both?) from what i've read this seems to be the problem...im checkign this weekend for boost leaks too. and theres no shaft play on my t25, so i think the turbos fine.

 

[lazylaser]

Well, I think you would only want to replace the front 02 sensor, because I'm assuming you're not going to want to use the rear one with the aftermarket exhaust, so why bother replacing it if its not going to be functioning anyway?


I'm pretty sure you disconnecting the rear 02 is causing the CEL but you should be able to check the CEL with a voltmeter (I know you can on 1g's, but I'm not sure about the 2gs check your Haynes manual). I think you can also bring the car to advanced or autozone and have them check the CEL or find a friend with a logger.


I'd check for boost leaks first, if there are none then consider a new 02 sensor. If you're running extremely rich that can hurt power drastically, so that might explain your power loss. I think the power loss after the intake install might be conincidence, assuming there is no boost leak.


Just to be sure, you did connect the bov return tube back onto the new intake right?

 

[NellySTL281]

yeah, i did reconnect the bov to the intake...thanks for all your guys help, im gunna run those tests and then maybe consider a new o2 sensor...my rear one is still functioning too (in my new exhaust)

 

[oldman]

...im checkign this weekend for boost leaks too. and theres no shaft play on my t25, so i think the turbos fine.

No need to guess at all, there are simple tests you can perform to eliminate them one at a time.

1. Make sure the wastegate is completely shut by puling the actuator arm off and observe the position of the wastegate lever when the arm is on and off. If everything seem to be fine and the problem still persists, goto step 2.

2. Disable the wastesgate by removing the hose between the mbc and actuator and plug up the nipple on the mbc and test run. This should result in uncontrollable boost so make sure to let off the throttle at about 17psi. If problem solved, you have a faulty actuator that opens prematurely. If problem persists, goto step 3.

3. Perform a completely boost leak test , fix all leaks until system holds 20 psi for at least 30 seconds. If problem persists after this, you have a dying turbo.

IMO It's either a bad turbo or huge leak, if you follow 1,2 and 3, you should be able to find what you're looking for. good luck.

 

[xcelr8n]

I agree with old man, and I think myself that youre problem sounds exhaust related, either a leak before the turbo, or something to do with the wastegate. I had a similar problem and what it ended up being is a slightly stuck open wastegate... good luck.