Beginning of this week I was boosting 7-8 psi, now only 4-5psi.

This problem happended after my brother replaced these:

http://www.fcpgroton.com/product-exe...ategory_id/215

http://www.fcpgroton.com/product-exe...ategory_id/215

I am assuming it is just a matter of tightening an upper IC hose or something of the sort. I don't think he needed to unroute the sysytem but he did.

Turbo still spools like normal, however, it will not kick in at higher rpms like it did before. It used to boost normal up to 70 mph then lag and now it will lag after 60 mph. I'm guessing that is just a result of a leak. Everything acts as if I had a turbocharger that only boosted 4 psi. What I am trying to say is that it is still a very clean boost.

I wanted to ask... What are other connections I should check? Could he have possibly adjusted the wastegate by accident?

 

How does it shift? Normal? Hard(ish?)? Does it seem like you have the same torque valuees?

 

The shifting is like it always was.

About the torque:
The turbo spools at the same time as always but just doesn't pull the car forward as fast and hard as it used to. I figured that was just because of the missing 3 psi.

 

check all the hoses...make sure they are holding good.

 

+1. Lack \of torque is the unequal air volume the maf sensor is sayingits pulling in.

 

Total newb question but how many hoses and which ones (if you could tell me they run from here to here that would be awesome)

 

5 hoeses total. someone try and look up a diagram

 

Diagram would be great for this thanks guys

 

just follow the tubes from the turbo to the IC, to the ic to the TB

remember it is a bottom to top ic

 

Just these hoses?

 

Yes check them. Espically the one going to the throttle body.

 

I'm checking today but if I find no leaks, what else could it be? I mean take into consideration it dropped 3 psi in one day.

My bro definitely changed something. Is there some kind of adjustment that would turn down the boost if there is no leak? I was thinking wastegate but I don't think he is dumb enough to adjust that, but who knows.

 

Not unless ironically the bypass valve just went bad.

 

So this doesnt make sense....

I uninstalled the stock turbo tubing and reinstalled new tubing along with t-ing into it for my aftermarket gauge (didn't want two gauges running from the turbo tree itself).

1. I fire the car up and get a check engine light. I also notice the car idles rough. I drive it anyway and only get 4 psi of boost like I have been since last week.

2. Come home, check the CEL -- misfires in cylinders 4 and 5. Reset the CEL.

3. Drive again. Idles fine. All of the sudden I am getting 6 psi of boost. I can not make sense of the situation in my head.


Although it did used to get 7-8 psi of boost so I am still misisng some boost. Can anyone make sense of this situation? I'm sure it sounds like I am making stuff up the ways events have played out recently.

 

After reading the last message note that even thought I am getting 6 psi, there is still a noticeable lack of torque.

 

this makes total sense. you have a firing issue on 4 and 5, thus less exhaust hitting ur turbo, thus less boost. and with 4 and 5 having an issue a rough idle would seem normal... and also a loss of power....

toss in new plugs, if that doesnt work go for new wires.

 

Never really pieced it together like that. Well Done!

But how do you explain after I reset the CEL yesterday everything ran fine? And it is still running fine today.

Would this also explain why when it was idling rough the aftermarket gauge bounced around at -20 inHg when there was no throttle action? It doesnt bounce anymore now that my car is running fine but when it was running rough yesterday I had that problem.

I will pull and check the sparks after work today.

 

Bad injectors leaking down into the cylinders causing the misfire?

 

But could the CEL have been a fluke? I mean after I reset it the car ran a hell of a lot better. While running with the CEL, the car idled rough and poured brown smoke out of the tailpipe while boosting 4 psi. After reseting the CEL, no smoke and no rough idling while boosting 6 psi.

I don't see how that would happen with bad sparks or a bad fuel injector.

I would say the car is fixed because I am only 1-2 psi off of what I was early last week but I still notice a lack of torque and it seems that the boost doesnt build as fast as it used to.

 

Maybe Mass Flow is going bad.