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Boost problem RB25det neo

BiggestRon22
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BiggestRon22 Explorer

BiggestRon22

Posted
Posted

Hello, I have a s2 rs4s stagea and I’ve been noticing issues with my boost after installing a gauge for it.

 

when I start the car up, let it warm up and then drive I usually get around 8ish pounds but after driving it for a bit or getting the 8psi in 4th gears it’s like my boost gets cut in half and it will only run around 4psi which is a very noticeable difference.

im just confused because I haven’t done really anything to the car other than an exhaust and one of the fuel cut defencer, I also have my bov to atmosphere at the moment and was going to see if having it recirc would help or just blocking it off again like i originally had it. I’ve heard things about the boost solenoid and the lines for it but unsure which spot I’d need to look in.

 

any info helps greatly!! 
thanks in advance

 

-Ron

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GTSBoy Grand Master

GTSBoy

Posted
Posted
On 3/26/2022 at 2:53 AM, BiggestRon22 said:

one of the fuel cut defencer

Definite potential cause of problems. Get rid of it. You don't need it. There is Nistune in the world.

On 3/26/2022 at 2:53 AM, BiggestRon22 said:

I also have my bov to atmosphere at the moment

Yes. Well. Do....

On 3/26/2022 at 2:53 AM, BiggestRon22 said:

having it recirc

again, because, obvious reasons. Your ECU hates you for having it VTA.

On 3/26/2022 at 2:53 AM, BiggestRon22 said:

I’ve heard things about the boost solenoid and the lines for it but unsure which spot I’d need to look in.

This could be what is driving the boost drop, because the stock boost pressure is about 5 psi (on the spring) and the solenoid bleeds it up to about 7.

BiggestRon22 Explorer

BiggestRon22

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  • Author
Posted
On 3/25/2022 at 6:09 PM, GTSBoy said:

This could be what is driving the boost drop, because the stock boost pressure is about 5 psi (on the spring) and the solenoid bleeds it up to about 7.

Yeah I’m gunna have to guess that’s it’s the solenoid because it starts at 7 then goes to 5 then sticks at 5 so it’s like it’s runnin stock pressure all the time, thinking of getting one of the manual boost controllers too see if that helps at all but would rather fix it so it stays at 7 before that.

 

On 3/25/2022 at 6:09 PM, GTSBoy said:

Definite potential cause of problems. Get rid of it. You don't need it. There is Nistune in the world.

Still debating on a power fc or nistune, the plug and play with the hand controller is a big plus to me, and For nistune I’d have to drive 6 hours to get the board installed and hope they can get it done and tuned in one day cause it’s my daily driver hahaha

BiggestRon22 Explorer

BiggestRon22

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Posted
On 3/27/2022 at 12:35 AM, Ben C34 said:

Nistune mate. Hand controller in 2022 is a f**king joke. Don't you have  a laptop?

nah, actually only have a desktop pc. been lookin for a laptop so i could tune eventually but hard to find one that isnt complete garbage is hard.

Ben C34 Grand Master

Ben C34

Posted
Posted
On 3/28/2022 at 12:49 PM, BiggestRon22 said:

nah, actually only have a desktop pc. been lookin for a laptop so i could tune eventually but hard to find one that isnt complete garbage is hard.

Any laptop will run tuning software, the required specs are so small they don't even factor in.

Buying a power fc because you can't figure out how to buy a laptop is pretty out there.

  • Haha 1
GTSBoy Grand Master

GTSBoy

Posted
Posted
On 3/28/2022 at 10:19 AM, BiggestRon22 said:

nah, actually only have a desktop pc. been lookin for a laptop so i could tune eventually but hard to find one that isnt complete garbage is hard.

Take your pick

https://www.grays.com/computers-and-electronics/computers-and-it-equipment/laptops

BiggestRon22 Explorer

BiggestRon22

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Posted
On 3/27/2022 at 8:20 PM, Dose Pipe Sutututu said:

I always say this on Guild of EFI on Facebook, if the laptop can load up pornhub then it will load up any modern tuning software.

1920x1080 screen is good.

Lmaoo fair enough honestly thought the tuning software would use a bit more power, shows how much I know I guess hahaha

BiggestRon22 Explorer

BiggestRon22

Posted
  • Author
Posted
On 3/27/2022 at 7:59 PM, Ben C34 said:

Any laptop will run tuning software, the required specs are so small they don't even factor in.

Buying a power fc because you can't figure out how to buy a laptop is pretty out there.

Honestly thought they needed more power hahaha

GTSBoy Grand Master

GTSBoy

Posted
Posted
On 3/29/2022 at 12:11 AM, BiggestRon22 said:

I’ll be checking marketplace pretty quick here hahaha

In all seriousness, near new 11th gen i7 15" laptops go for ~$500 (plus some costs) at auctions all the time. You'd be mad to go to bookface ripoffplace which is where people who buy them from the auctions resell them for a profit.

czeno Explorer

czeno

Posted
Posted

My RS4 had boost leakage at the throttle body rubber union, it was hardened by time & heat. Perked up a bit after sorting that. A bit later head gasket failed, hmmm. That teardown also revealed exhaust manifold warpage (leakage was un audible). Different beast now.

BiggestRon22 Explorer

BiggestRon22

Posted
  • Author
Posted
On 3/28/2022 at 4:23 PM, GTSBoy said:

In all seriousness, near new 11th gen i7 15" laptops go for ~$500 (plus some costs) at auctions all the time. You'd be mad to go to bookface ripoffplace which is where people who buy them from the auctions resell them for a profit.

Damn didn’t know that, will be checking the auctions soon then!

 

On 3/29/2022 at 1:30 PM, czeno said:

My RS4 had boost leakage at the throttle body rubber union, it was hardened by time & heat. Perked up a bit after sorting that. A bit later head gasket failed, hmmm. That teardown also revealed exhaust manifold warpage (leakage was un audible). Different beast now.

Ahhh yeah I don’t doubt I have a few leaks goin on, gunna check my throttle body and manifold/turbo gasket soon! 

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