Downpipe installed now wont boost

[bigeazy6969]

So i got a downpipe made today but now i have problems. When i get on the gas it will only hit 5psi in 1st gear then fall flat on its face. It does the same thing in all the rest of the gears but I can hit 9psi. Befor I had the downpipe made and installed it was running open O2 housing and boosting 18psi. Spool up was fast and sounded great. Now it cant get out of its own way befor it sputters on me. I checked all the vacumm lines, wastegate, MBC, basicly everything I can think of. Any help would be great.

 

[Sp1kE]

did the wastegate arm pop off the turbo?

 

[bigeazy6969]

Nope running external 38mm.

 

[Deuce_three]

do a boost leak test

 

[bigeazy6969]

did that too and everything is sealed good.

 

[kottyking]

Check the connections on the MAF sensor, just to to be sure something didn't come loose when you were in there switching the down pipe out. Earlier you said you had open dump off the o2 housing before, has that changed?

 

[bigeazy6969]

I did check all the sensors and everything seemed tight. As far as the exhaust all i was ruinning was the o2 housing right off the turbo and thats it. All the exhaust shop did was make me a 3in downpipe but it in and now its messin up on me.

 

[AlaskanDsm]

Nice, another DSM from my home city!! be selling my beat up GSX for parts this summer if your interested...

issue at hand... Possible the O2 sensor got messed up somehow? Is it possible that the exhaust shop take off your O2 housing by chance? It could be throwning false info to the ECU which could be causing it to fall on its face. If you have a logger, you might be able to see if you have any weird numbers.

Does the car Idle ok and only get messed up when you try to drive or is the idle effected as well?

 

[bigeazy6969]

The cae idle's great and runs great too just as long as i dont get into the boost. Im thinkin about taking the exhaust back off and seeing if that changes it.

 

[beniger]

so now you are running just a down pipe?

 

[bigeazy6969]

Im running full exhaust now. Befor i was just running the O2 housing.

 

[bigeazy6969]

So i took the exhaust back off and still does the same thing. I just dont understand whats goin on with it.

 

[AlaskanDsm]

Well, I would think that it would have to do with something that the exhaust shop did. I would think that it is possible that they damaged the O2 sensor possibly or it was unplugged. Do you have a logger you can try to check your numbers when you are driving the car?

Unless there is some huge strange coincidence that you have some other unrelated issue as far as what the exhaust shop touched sounds very unlikely.

 

[bigeazy6969]

I just bought a logger so ill have to wait to see what that is showin me. Im almost at the point of giving up. Damn i hate to love these cars.

 

[AlaskanDsm]

No such thing as giving up on a dsm!! If I were you, I would call the exhaust shop and inform them that ever since they installed the exhaust on your car, you have been having issues with your car and you would like to know what work they did on the car and how and maybe you can trace some steps. If you don't mind me asking, what shop was it that did the work?

 

[twalters09]

it sounds like it could be a coinsidence, the o2 sensor could have just taken a dump on you at the same time you put the down pipe on, sometimes these things happen and it leads you to the wrong direction when it was just something that wouldve happened anyway, if you have acess to a good o2 sensor plug it in and see if that fixes your problem, if not i would order a new one and give it a whirl, keep us posted, best of luck

 

[JMiller]

I would suggest hooking up an o scope to your o2 sensor to see if it is switching properly if not, then go get a new o2 sensor.

 

[bigeazy6969]

Thanks for the suggestions guys. Im up for trying anything right now. The O2 sensor is kinda new but ill still try it.
Oh and as for the exhaust shop i took it too Fairbanks Radiator and Muffler.

 

[AlaskanDsm]

I remember the business name but can't place the location. When I google it, Auto Trim Design comes up on street view haha.

 

[DSMopar]

Save your time and money it's not the o2, check all your wastegate lines etc make sure they didn't mess with anything. Are you sure you did a boost leak test properly?


Failing all of this, it's possible the ECU was damaged if they welded the exhaust on your car.

 

[bigeazy6969]

I have checked everything for the wastegate and everything seems to be working right. I did finally get the code from the CEL and its code 31 which is the knock sensor. so thats my next step. but if this doesnt work i will be at a loss so I am open to any more sugesstions. thanks!!

and its right next door to auto trim design

 

[AlaskanDsm]

I think at this point you should get that logger hooked up and check all the numbers and find out if you have any weird ones or anything that stands out. It is very possible that the knock sensor could have gone out on the car or is unplugged. Check the A/F ratio and see what kind of knock you are detecting if any. Thats where I would start.

 

[bigeazy6969]

Yea im definantly gonna see what the logger has to say. The only bad thing is all these sensor's are kinda new and the A/F ratio is good. Atleast thats what its tellin me with the guage. So ill just have to wait and see whats up and .

 

[EclipticalGS]

any sort of vacuum leak dealing with your wastegate pressure source/mbc would only make boost higher than before. Im wondering if your wastegate flapper is opening for some reason too early.

What are you tuning with?

 

[AlaskanDsm]

Hey did you ever resolve the issue?