Stock n75J valve overboosting??

**CupraGTi** · 01-02-2016, 12:32 PM

Ok guys I know I had an obsession with trying to get a MBC to work.. ive realised its not a great idea. And although I was getting 13psi and it was holding and everything, it didn't feel strong. I have ditched the MBC

I've got the setup running just the n75j valve... 2nd 3rd gears holds 10psi, get into 4th and 5th and it will hit requested boost hold it for a bit then start ramping up...

Whats going on??

ECU confused?

reset ECU?

n75 stuffed??

**Lito** · 01-02-2016, 03:59 PM

N75j is not the stock valve. The n75e is the correct revision for our engine iirc. Are you sure you have the thing plumbed in the correct way? Make sure your actuator is set to the standard 5psi. Screwing this up will give you all kinds of boost issues. If you unplug the n75 electrically it will go into open default mode, you should see 5psi and hold that till redline, nothing more. If it creeps above 5psi someone has cranked you wastegate, I suggest looking up how to adjust your preload if this is a case.

**CupraGTi** · 03-02-2016, 07:42 PM

cheers mate,

ive been playing around with a MBC and with it running the show by itself with the n75 plugged in electrically, but not actually using it to control boost. The MBC would hold the 13psi all the way to redline, so I don't think its the wastegate flapper, rod, or actuator itself....

I think I've just upset the solenoid. WIll get vagcom on it tomorrow.

Thanks

**CupraGTi** · 03-02-2016, 07:43 PM

and yeah I know the J isn't the stock solenoid. And you have to turn it around basically to hook it in. I do have the valve set up correctly, I just think I've upset it.

Time to just save for rods, turbo, and custom code. end of drama's.

**Lito** · 04-02-2016, 09:35 AM

Originally Posted by CupraGTi

and yeah I know the J isn't the stock solenoid. And you have to turn it around basically to hook it in. I do have the valve set up correctly, I just think I've upset it.

Time to just save for rods, turbo, and custom code. end of drama's.

Just because the mbc holds boost doesn't need the wastegate is set correctly. I suggest you plumb everything back to stock, unplug the n75 electronically and see where your boost is at. If it holds at around 5-6psi your wastegate is fine if not then adjust it so it's set at 5psi. This is what your software is expecting and any deviation too large from that will make the ECU freak out.- the n75 is basically just a bleed valve but it's controlled by the ECU, I doubt it would fail intermittently they usually just stick open when they fail. Please don't go adding a big turbo and another tune before you understand how the stock setup works, you'll just be creating more trouble for yourself.

**dubster99** · 04-02-2016, 11:39 PM

carlos Im slowly learning about turbos now and I went ahead and did my conversion haha

**CupraGTi** · 08-02-2016, 02:30 PM

but I want more boost. economical, efficient non-k03 boost. I see no point in pushing 18psi through a k03... sorry. I'd rather 13psi through a frankenturbo and make more power. I understand how turbocharged motors work. its just this n75 is playing up.