Street King

OK I just gutted my cat. This was happening before I did the cat. It seems everytime I add something to help free flow the exhuast it spools slower. As of right now I'am getting 8 psi like a rock. Nothing over nothing under. It takes a long while to build boost, I'll be at 8 psi around 4500 rpm. The boost transitions deep into like 4-5 psi before rising agian to 8 psi. I have no idea where to begin. If someone can please help me. I've been working on cars all day then this happens, really pissing me off. Pictures would be nice, and LAYMEN'S terms are what I need. Please just leave some ideas.

P.S. I did a major search and was seeming like a hose under the UIM popped off or something.

legendr35

I changed out the check valve under the vacuum chamber and my boost patterns were back to spec...

rpm_pwr

check:

1) Is your charge control actuator rod being pulled in at idle? (This checks the vaccuum chamber system)
2) Is the turbo control rod pulled into the actuator? The exhaust pitch should tell u that.

It sounds like the car is locked in 2nd turbo mode. But then again boost is low also so you probably have a boost leak somewhere also.

Check:
y-pipe connection
x-over pipe
CRV
IC and feeder pipes for leaks.

-pete

Street King

Did you have the same symptoms as me?

1: Where and what does a charge relief valve look like? Is this the BOV?
2: Where and what does a turbo control rod do and what acuator? What should the exhuast sound like if this is a problem?

I seriously think it's an IC hose problem. I had one before and it wouldn't boost but like 1 psi. I think I might have a small pinhole letting air out. I just ran into this problem so I havent got dirty under the hood.

rpm_pwr

LOL pinhole! Nope it'd have to be bigger than that!

The CRV looks exactly like the BOV except it comes from the 2nd turbo not the y-pipe. It bleeds off boost from the 2ndary before it comes online.

The Turbo control rod is under the turbos. It has two hoses that connect to it and is used to select wich turbo to direct exhaust at.

So, is the charge control (mounted ON the y-pipe AT the junction) rod being pulled in? If you're unsure, look at it and get someone to turn the key from ACC to ON and back again. You should see it move. Alternatively, just rip the vac hose off the CRV and listen for vaccuum.

-pete

Street King

OK this is what I got so far. Went out there trying to look under the UIM. All hoses seem to be connect. RPM thanks I will give those a try. The CRV is already vented so I'll listen for vacuum.

Ok after this I fired her up. Idled fine. Now when I reved it, after I let off and the RPM's are going down I hear drunk bumps(this is what I call those things on the side of the road that tell you, you are about to run off the road. When your drunk swervin' you will hit them and make a sound, hince the name) or maybe a mooing? This only happens for a little less than a second from the falling revs. I have my hose disconnected from the airbox(on the right side standing in front of it.) I was to understand this hose just vented air and I didn't need it. So I took it off. I thought the sound was coming from it so I put the hose back on and it made the sound just a little quieter. I know this noise has to be it, if anybody can help me out?

Street King

Can anyone help me diagnose this please?

rpm_pwr

I'll try again.....

does the charge control pull in YES OR NO???????????

-pete

Street King

Ok RPM due to my limited knowledge of the plumbing of the twin turbo's I did the best I could at 11:00pm with a flash light and a brother. I did what you said, I couldn't find anything pulling. Heard noises like things were working in the area but I didn't see anything move on the CRV or the plumbing to the y-pipe. I was reving it and didn't feel any vacuum or air blowing out of the CRV. Also the 2 hoses that come off of it to the y pipe. The big one was really loose. Almost like I could pull it off with my fingers. I could push it around with my index finger. No stiffness of it clamping to the y-pipe at all. Could this be what you are talking about RPM? Sorry man I'am new to diagnosing turbo problems. Didn't want to start pulling off hoses because it was late.

When I was reving it it still was making a mooing sound. Found out it was the air pump and no more mooing and a little more power. Could have been the night air I don't know. It still hitting 8-4-8. To tell the truth it feels like it's in NON-SEQENTIAL mode. No kick at 4500 rpms, just a straight pull till red line. Thanx for your help so far RPM.

My vacuum got even smaller. UP TO -14 vacuum on the boost gauge!!!! Had a little lumpy idle after a few pulls.