Loss of power need help bad

[89gt02]

Ok guys I really need help I have a 97 gsx and just bought it. It has been having issues since I got it and has terrible power loss under boost.
Mods done to the car is injen hard pipe kit and fmic. And car is auto tranny.
Here are the codes I have throwing my cel.
P0170, p0141, p0400, p0505, p1104, p1105.
The wastegate solenoid/bcs is missing so I have a mbc set to 14.
I do have aftermarket guage too .

The boost hold 14 very good I dont have boost leak at all.
But under boost it has no power and feels like I dont have a turbo.
I got brand new knock sensor and it didnt do nothin. I thought that was my issue pulling timing.
I dont know ### to do ive had dsms that were all stock and was way way way faster than this car.
I need help guys I been trying to fix this everyday since I got this car.

97 gst sorry my mistake .

 

[Talyn]

Somewhere in tech articles is a list of all the codes and what they mean, I would start there, that is a lot of codes. And a lot more info is needed on the car's setup. Ie. stock BOV? stock turbo? etc.
The stock BOV won't hold past 12 or so psi.

 

[ChiTownHussla]

subbed. I am having the same issues since I got mine

 

[Eagle96TalonTSi]

I would still do a boost leak test regardless of how you think it feels under boost. Running "14 lbs" boost on a T25 is pointless on a stock BOV because like ^ said, it holds 10-12 psi under boost. If you dont have a wideband, you should not have a MBC. Do like I did and turn the MBC all the way out until you get a WB sensor.

You should also verify what your codes mean and fix everything before you even put the car IN boost, because youre likely making your problems worse and could end up spending a lot more money that you wouldve.

Park the car. Decipher the codes (), Fix the problems. Run a BLT and vacuum leak test. Basic maintenance.

Until youve done this youre not going to get any real help from anyone here because while it MAY sound like something else, it has major symptoms of a boost leak and/or it could be related to your CEL codes.

Btw, when I bought my car, it felt and sounded consistent under boost. Made a BLTester, strapped it on and sprayed that bad boy down... turned out the coupler attaching my lower IC piping had clamps not even screwed on. I also found 5 or 6 other locations that were leaking badly. Ever since I fixed all the boost leaks its a different car and I cant even get traction until middle of 2nd gear.

 

[89gt02]

I have a greddy bov and I know what all the codes mean.
One is 02 sensor 2 and it dosent control fuel mapping one is that stock boost controller and one is iac and one is fuel pressure solenoid. I didnt think any of those could cause a major power loss like im having.
And I have the t25 turbo and its new.
Sorry I didnt mention this earlier

I will try another boost leak test and see ### I find.
And also I think the car is running rich judging by the black smoke and the smell

 

[n0de]

I have a greddy bov and I know what all the codes mean.
One is 02 sensor 2 and it dosent control fuel mapping one is that stock boost controller and one is iac and one is fuel pressure solenoid. I didnt think any of those could cause a major power loss like im having.
And I have the t25 turbo and its new.
Sorry I didnt mention this earlier

I will try another boost leak test and see ### I find.
And also I think the car is running rich judging by the black smoke and the smell

Change the IAC and the fp solenoid throwing a code can cause issues like the one you are describing if something is (god forbid) actually wrong with the fuel pressure solenoid.

 

[Tyeler18]

PO141 o2 sensor heater Circuit Malfunction (Bank 1 sensor 2)
PO170 Fuel Trim Malfunction
PO400 EGR Flow Malfunction
PO505 Idle air/control Motor Malfunction
P1104 Turbocharger wastegate solenoid Malfunction
P1105 Fuel Pressure Solenoid Malfunction (turbo)4g63t

There's all your codes. I'd assume you have most of the emissions lines deleted Fuel pressure solenoid, obviously the wastegate solenoid, is the egr deleted as well?

You have an issue with the downstream oxygen sensor heater, but that won't cause your issue. Now the fuel trim issue is the one to look into. See what's going on with that, and it looks like you possibly have a bad ISC.

If the fuel pressure solenoid is sticking closed it won't allow manifold vacuum to reach the FPR, this won't allow the FPR to raise fuel pressure under load, and will cause higher fuel pressure at idle. It'll cause it rich when not in boost, and lean when in boost. Which could very well be the cause of your fuel trim code. Try bypassing the solenoid and see if it fixes it.

 

[89gt02]

Will do man thanks ill try it tomorrow ill keep posted and see what happens.

Ok guys I bypassed the fps and no change. Im on my way now to make boost leak tester

Any ideas on ### wud cause the fuel trim code to come up?

 

[Talyn]

Either the car is running lean or the ECM thinks it is, and if it is running lean, its either getting unmetered air(boost leak for example) or not enough fuel. Though I am pretty sure mods that increase air flow would also cause fuel trims to rise.

 

[Cdc1221]

Unmetered air entering the system is usually from a leak btween the mas and turbo, not a boost leak. I wouldnt think that would throw a code though.

 

[neeley67]

I know this is an old post but did you get this fixed? my car has the same problem I have changed my cas many times. I have no boost leaks and a very small leak on throttle body on a sensor but it should not effect it like it is.i was in a front end wrecka few weeks ago checked all piping and no leaks, I am running extreamly rich like the car is making up for too much air. but no real power. my down pipe was glowing red the other day and I thought my catalac converter was clogged so I put a new exhaust on and it still has no power. it is all most like the car is a n/a. and still not even enough power to be an n/a. any help would be very much appreciated because i am running pout of ideas. btw no mods except walbro 190 and an emissions delete. and running extream ly rich