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2G BOV Obtained, More Issues Arise

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cornboy

Proven Member
49
6
Feb 28, 2020
Manhattan, Kansas
So in the span of time between this post and my last, I bought a Greddy Type RS off another forum member, I also bought an appropriate mount for it to be welded into my intercooler piping. I also bought vacuum hosing so I can actually use my wastegate, and my blow off valve.

So the valve is mounted and both the waste gate and blow off valve are hooked up to boost a la this diagram.

dsc00275-jpg.409569


The issue now is that I can only get up to about 55mph before it feels like its choking out or something going wrong.
It doesn't want to go any faster, regardless of gear. And if you try it kinda sputters and coughs like its being choked out. I'm thinking it may be the BOV leaking air from the intercooler back into the intake, but I have no real way of testing. Should I rebuild the BOV to see if that fixes it, is it an issue endemic to the Type RS, or is it because the BOV is hooked up improperly?

I should note, I have tried turning the adjustment screw on top nearly all the way to hard, with only a few threads poking up above the lock nut.
 
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This is wrong. BOV & wastegate can not share the same line. Run the BOV by itself from the manifold. The intake manifold (after the throttle plate is not a boost source. Boost source is after the turbo compressor. The TD06H compressor cover should have a nipple on it for the boost source hose that ends at the wastegate depending on any boost controller. Read through this thread. It has from the factory & ways to eliminate emissions.
https://www.dsmtuners.com/threads/taboo-speed-shop-vacuum-diagram-and-removal-for-1g-and-2g.198327/
 
What mods do you have fuel wise?
I was told I have aftermarket injectors, but considering I just bought this a month ago, I haven't had an opportunity to check, but I assume that it's the stock fuel system.

Bov and wastegate do not use the same line.
This is wrong. BOV & wastegate can not share the same line. Run the BOV by itself from the manifold. The intake manifold (after the throttle plate is not a boost source. Boost source is after the turbo compressor. The TD06H compressor cover should have a nipple on it for the boost source hose that ends at the wastegate depending on any boost controller. Read through this thread. It has from the factory & ways to eliminate emissions.
https://www.dsmtuners.com/threads/taboo-speed-shop-vacuum-diagram-and-removal-for-1g-and-2g.198327/
Thank you, and especially thank you Mello for showing me where I can find that diagram. A lot of the vacuum lines have been f***ed with, or sealed off, and a lot of the engine bay is modified so that second diagram is really helpful for figuring out what vacuum lines go to the blow off valve, and which go to the waste gate.
 
I was told I have aftermarket injectors, but considering I just bought this a month ago, I haven't had an opportunity to check, but I assume that it's the stock fuel system.
Don't assume anything. Assumption is the mother of all f*ups. If you have larger injectors you must have a way to tune.You need to figure out what all has been done
 
Regardless. The blow off valve and wastegate should not share same line. The blow of valve should have its own line from intake manifold, And wastegate should have its own only boost source so a line from compressor cover or intercooler pipe before intercooler.
 
Regardless. The blow off valve and wastegate should not share same line. The blow of valve should have its own line from intake manifold, And wastegate should have its own only boost source so a line from compressor cover or intercooler pipe before intercooler.
Okay cool, thank you man. I'll get that done tomorrow and report on results tomorrow.
 
1G blow off valve > *insert any aftermarket blow off valve here*. If you fear it's leaking boost pressure back into the intake, do the Dodge Garage Mod and that will be the end of that issue.

Regardless, a fuel pump doesn't really have a set fuel consumption limit at 55mph so unless something else is hindering flow or preventing proper pressure from being built, like a clogged filter or bad regulator. I highly doubt someone would've installed larger injectors without upgrading the pump, but you never know...the pump itself can also be going bad, or the line carrying fuel from the pump to the bulkhead may be split or leaking pressure back into the tank.

But as others have said...never tee into the BOV signal line for any reason.
 
Update: I re-ran the vacuum line as per the diagrams Mello linked, the intake manifold directly to the BOV, and the compressor nipple directly to the waste gate actuator. However, the problem still occurs. I did decide to try and drive it on some nearby highways just to see if it could get up to speed and it can, just any boost pressure in 3rd 4th or 5th causes it to sputter. Since the car has ECMLink I will take some data logs later, any advice on what specific number would be most useful or should I just get as much data as possible.

1G blow off valve > *insert any aftermarket blow off valve here*. If you fear it's leaking boost pressure back into the intake, do the Dodge Garage Mod and that will be the end of that issue.
I would do this if I had the stock BOV, or was making anymore than 7PSI of boost pressure.

Regardless, a fuel pump doesn't really have a set fuel consumption limit at 55mph so unless something else is hindering flow or preventing proper pressure from being built, like a clogged filter or bad regulator. I highly doubt someone would've installed larger injectors without upgrading the pump, but you never know...the pump itself can also be going bad, or the line carrying fuel from the pump to the bulkhead may be split or leaking pressure back into the tank.
I still doubt it's a fuel issue, as before I installed any BOV it had no issue accelerating.

Thank you all.
 
Regardless, a fuel pump doesn't really have a set fuel consumption limit at 55mph so unless something else is hindering flow or preventing proper pressure from being built, like a clogged filter or bad regulator.

I just wanna post this for posterity and say he was right. Decided to do one last look through and see if there was anything that might be out of place, and it had been a while. Checked the vacuum line that runs from the intake manifold to the boost gauge and the from the boost gauge to the fuel pressure regulator. That vacuum hose wasn't attached to the regulator.

So I guess that leads back to Mello's original post. Double check literally all your vacuum lines.
 
Just out of curiosity, are you positive you got an authentic Greddy RS blow off valve? The knockoffs are close imitations these days...
Does your BOV have a large gold/brass color ring on the bottom side where it sits on the flange? If not, it's a fake. And they don't work as good. The action is sticky.
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Okay, so I didn't actually solve my problem with this. I'm still left with no idea what is causing my car to run so poorly and would love it if any of y'all could help me out with some knowledge.
 
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