problems dont walk alone...

[kirvis]

My UrS6 started getting a vibration at speed ended up being an outer front cv on the drivers side from too many hard turns on sprint courses.

Missfire also check for fouled plugs, poor spray pattern on injectors, and the one that catches most people out is have a look at the MAF. Where the thin wires are sometimes one of them lets go ever so slightly and looses contact when a large quantity of air suddenly has to go past it. i.e. when you put your foot down. Real common problem on these cars often misdiagnosed for something else.

thats the list i have changed so far to sort it:
*lambda sensor
*sparks
*injectors
*MAF
*N75 valve
*map sensor
*coil pack
so i dont know what else can i do about it...
to sort the vibration i bought a rear diff mount and bushes today, so hopefully will fit them on sunday along with the prop shaft bearing an d will see is that going to change

[prj]

Are you 100% sure it is misfire and not boost or fuel cut?

[kirvis]

Are you 100% sure it is misfire and not boost or fuel cut?

i dont think its a fuel cut as im running LPG as well and on LPG its even worst. but boost hmmm... dont know... how to check it?

[prj]

With a boost gauge.
If when it happens your boost goes to 0.4 bar (1.4 bar absolute pressure), then you have fuel cut.

This is only the case if wastegate has not been tampered with though.

[kirvis]

well with the pedal pressed half way the standard boost gauge shows 2.0

[s2_bo]

You have a digital boost gauge on the auto check in the dash. Just look at that and see what its reading when you put your foot down and it starts to bog down.

[kirvis]

just like above 2.0 cant tell you whats it like with the food down as it just starts misfiring.

[prj]

Foot half down and already 1 bar boost?
There is your problem

Please undo whatever you did to your wastegate and make sure N75 is connected properly.
Seems like you have simply boost cut... you should never have 1 bar boost with half down throttle.

What software is in your ECU? Standard? chipped?

[kirvis]

its all standard apart from forge BOV , and Upgraded N75

[prj]

You have a BOV?
And you are venting the air to atmosphere?

[kirvis]

???????

[prj]

???????

The BOV that you have, you are venting the excess air into the atmosphere, and not circulating it back after the MAF?

If you do that, it explains everything.

[kirvis]

but i was using this bov for about a year and it was ok before

[prj]

uhu... "OK"...
With a BOV you flood your engine every single time you let off the throttle.

What you are describing sounds like boost cut. Put a stock WG spring into your wastegate, or "unscrew" it, it's obviously not a 0.4 bar spring in there, if you have 1 bar of boost at part throttle.

Take that BOV and throw it into the garbage bin and buy a proper metal bypass.
If you like that annoying BOV sound, then get a cone filter and you will also hear that sound with a bypass.

Until you do all that, stop complaining

P.S.
It's possible the ECU can't handle your "upgraded" N75 either. Why would you even "upgrade" it? Stock one worked fine for me at like 2 bar boost.
I don't think that's very likely though, because the N75 is a very simple device and you can indeed swap many of them...

[kirvis]

ok ill put the standard bov back on. so u recon it should change straight away?