No boost help

So I had been making boost fine but I as replacing seals and gaskets that we're no longer sealing and anyways I got everything put back together and car runs great fires up better then it ever has since I have owned it drives good but it does not make any boost the highest it got was -0.27 on the Cobb tuner

 

I have checked all the vacuum lines everything is connected correctly according to the diagrams and not leaking all new lines

 

Turbo has no shaft play and spins free

 

The only thing I found when checking everything was my oem BY pass valve was not working the valve would not move from the closed position now correct me if I'm wrong but I thought if it was closed i would still make boost

 

so I don't think that's why it's not making boost but I could be wrong

 

My new BPV will be here Thursday so when I get that I'll put it on and do a smoke test to see if there are any leaks that I can't hear

 

 

Turbo

I would start with a smoke or pressure test to make sure nothing is leaking too bad. How did you determine the bpv was stuck closed?

 

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I would start with a smoke or pressure test to make sure nothing is leaking too bad. How did you determine the bpv was stuck closed?

 

Sent from my SM-G970U using Tapatalk

 

Determined it was stuck closed due to in was in the closed position and could not get it to actuate and open with compressed air it worked before and have checked it with my compressor before and it had worked just fine as far as I could tell but this last time it wouldn't move at all

 

Yeah the smoke test is all I got left to try and figure this out

 

Who knows maybe I have missed something/ overlooked something it just baffles me on how great it is running yet something is causing it to not make boost I made sure my oil feed and turbo blanket are clear of the wastegate arm as well

 

I'll figure it out I just figured I'd post seems how I didn't find a post for it and see what other people had experienced or found to be the culprit if they had the same issue at some point

 

Thanks for the reply

Bypass valve would be tested with vacuum not pressure. Any CEL? Did you take the car for a drive to check for boost or just rev it? You’d need a big leak or broken turbo to make no boost at all. Are you using a invidia downpipe? They have a divider that the waste gate flapper can get hung up on and stay open.

Bypass valve would be tested with vacuum not pressure. Any CEL? Did you take the car for a drive to check for boost or just rev it? You’d need a big leak or broken turbo to make no boost at all. Are you using a invidia downpipe? They have a divider that the waste gate flapper can get hung up on and stay open.

 

No I'm using the Cobb high flow catted down pipe and it does not have the decider in it like the invidia nope zero cels if you supply pressure to the vacuum side it would open like it had before when checking it no I don't just rev it I have gone in several drives checking things and driving again trying to find any leaks and listen for anything but so far the BPV is the only thing I could find that was not working and leaking but was a small leak and turbo spins free by hand with zero shaft play

 

Thus is the first time I have ever not made boost since I purchased it in 2013 so this is new for me normally I have to baby it so I'm not over boosting

Definitely scratching my head on this one. Any odd sounds when you put your foot into it? Making no boost would make me think wide open waste gate flapper or pre turbo exhaust leak or big boost leak like i/c to throttle body hose. What performance mods other than Cobb dp? Up pipe, 3port ebcs, aftermarket intercooler?

 

Just so we’re on the same page when you say bpv you mean the recirculating valve on top of the intercooler not the wastegate actuator?

 

When I run into an issue after working on the car I think back on what I did. What was everything that you did? You said replaced some gaskets and what else?

Definitely scratching my head on this one. Any odd sounds when you put your foot into it? Making no boost would make me think wide open waste gate flapper or pre turbo exhaust leak or big boost leak like i/c to throttle body hose. What performance mods other than Cobb dp? Up pipe, 3port ebcs, aftermarket intercooler?

 

Just so we’re on the same page when you say bpv you mean the recirculating valve on top of the intercooler not the wastegate actuator?

 

When I run into an issue after working on the car I think back on what I did. What was everything that you did? You said replaced some gaskets and what else?

 

I have Cobb catted 3inch down pipe

Tomei ARMS MX7960f turbo

Perrin turbo inlet intake

Cobb v3 acessport

Crawford v2 AOS

Stage 2 /20% low Wastegate duty cycle

Checked on road tune / data log at local performance shop till I get a pro tune

Nothing crazy not much power

 

I was looking for the source or a possible oil leak found no oil leak but found that almost all my intake manifold seals showed signs that they might not be sealing so I replaced them I had also been getting a fuel odor on cold starts I checked the fuel injector seals and every single one was cracking apart so I replaced them took my time to clean everything and make sure things were seated right went back over my vacuum line diagrams and diagrams for the Perrin intake all that appears to be correct even if I give it wide open throttle it just sounds like it's being held back I can't hear any auditable leaks / hissing or sucking of air

 

I also replaced any brittle vacuum lines that I found while I had it apart so I didn't have to worry about taking it back apart for a while

And yes the BPV on the drivers side of the intercooler not the wastegate on the turbo itself Edited July 10, 2020 by 08legacygtturbo
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Electronic boost control? If not was the pill retained for that turbo? Did you replace the vacuum line that had the pill? I’d think without the pill it would still fall back on spring pressure and make some boost. I’d double check the boost control vacuum lines for proper connections if you took them apart.

Electronic boost control? If not was the pill retained for that turbo? Did you replace the vacuum line that had the pill? I’d think without the pill it would still fall back on spring pressure and make some boost. I’d double check the boost control vacuum lines for proper connections if you took them apart.

 

It was all my fault I didn't pay close enough attention when installing the turbo and trimming my oil return hose hose clamp came off and went into up pipe and got stuck in the turbine when I started it up putting turbo back on now luckily it did not damage the turbo still zero shaft play and spins really nice still and the blades don't even have a scratch on them thank you for all the input maybe it's a sign to not work on my car while I'm doing 12-13 hour nights at work and then only sleep for 2-3 hours

Wow! Glad you pulled the turbo back off. I had considered a rag but figured the car wouldn’t idle right with a major clog like that. No boost at all, no shaft play, no noise, no cels really had me at a loss.

Wow! Glad you pulled the turbo back off. I had considered a rag but figured the car wouldn’t idle right with a major clog like that. No boost at all, no shaft play, no noise, no cels really had me at a loss.

 

Yeah at first I pulled the down pipe to make sure the turbo would spin and nope so I took the turbo off and was like well crap hopefully that didn't mess up the turbo and I got lucky still no shaft play and the blades didnt even have a scratch on them she runs great now and I'm not overboostibg as much as I was so I'm sure all the work out seals and gaskets were part of the cause there only overboostibg to 23.57psi now not 27psi so I'm happy hope everyone else had a productive Friday or went for a nice drive I did both

Does the car make power still. Could be your boost reader line came off.