K04 boost pressure

[goodridge]

Hi guys, I've just got my AUQ up and running in my MK2 Golf with a k04-023 on it. It's running well but only holding 13-14psi. It does spike occasionally at 20-21 but then will die off again? Can anyone shed some light on it?

Cheers

 

[Willie]

Is this a remapped car (I take it it is from the spike pressure), have you spoken to the mapper

 

[shazz]

sounds like something i want to know as well..

i am running a mk2 golf 20vT,

what sort of boost should you run, what is safe?

When i spoke to Jabbasport they said 16psi is safe etc ?

 

[goodridge]

Well I've been playing again today. And at lunchtime, it would hold20-21psi and was absolutely flying! Come to try if after work again and it's back down to 14psi. If I disconnect the N75 it will spike 24-25 (too high I know) and hold 20-21ish. Is this a safe test for the N75 though? Does it mean its shot? Any help appreciated thanks

John

 

[Revo Kev]

John, it depends what the car is mapped for... however if the N75 does start going faulty it won't give you a fault code and can put you into limp mode. Are you mapped to suit the hardware spec? What (if any) faults are you getting?

 

[shazz]

John, it depends what the car is mapped for... however if the N75 does start going faulty it won't give you a fault code and can put you into limp mode. Are you mapped to suit the hardware spec? What (if any) faults are you getting?

i think he is running a Emerald Ecu, don't know if it has a limp mode

 

[Revo Kev]

Ah, in that case it's likely to be an N75 fault... put an MBC on to test and set it to hold what you please!

 

[shazz]

Ah, in that case it's likely to be an N75 fault... put an MBC on to test and set it to hold what you please!

sorry to sound thick, but whats a MBC ?? my cars going in for a map soon, i think i should check my N75 just incase, instead of getting there and finding out its buggered.

how can one test the N75 valve?

 

[Revo Kev]

Manual Boost Controller. There's not much you can do to check... you'd need to monitor the requested and actual boost values and if you're falling short of the requested value you might have a leak. However a typical N75 failure causes sporadic loss of boost (with no fault codes on ME7) and/or boost surging on acceleration (as if you're pumping the throttle!).

 

[shazz]

ah huh, i see..

well i guess judgement day is soon for it then lol..see how it performs

 

[goodridge]

I'm on OE (ME7) I've tried a new N75J but I have 17705 code no so I'm searching for leaks! Been reading a lot about leaks into the breather system and I'm fortunate that I have no servo on my G60 golf so I'm going to just cap the big hole on the manifold, and run the breathers to a catch can to eliminate that. Other than that I'm going to try a yellow spring in the DV I have been reading about.

John

 

[HTC]

I've given up with N75 valves and junked mine. Boost had never been right for one day to the next. I use an EBC now. Boost is perfectly controlled.

 

[goodridge]

Still got issues with this guys, eliminated the breather system. If I key off/on I can restore it back to good power ?