Megane Megane 225 cutting out under acceleration

[Josh lowe]

Hi my first post on here , I have a 2008 Megane 225 cup , I did a track day in it at the weekend and absolutely loved it , but in the last session it started cutting out under hard acceleration for about 2 seconds then the power would come back , if i put the pedal down to the floor gently it will pull all the way to the red line , but as soon as I try to accelerate hard it cuts all power off , has anyone ever come across this ? Thanks in advance, josh

 

[andybond]

Could be a few things this @Josh lowe
1) N75 valve that bleeds off the boost is failing
2) Injectors are on the way out

I would be looking at option 1 first. Sounds like overboost protection or something of that ilk.

 

[Josh lowe]

Thanks Andy ile try that next We're is best place to get the valve from ?? Thanks

 

[andybond]

Just about anywhere. Its generic. I would try one from a car that is being broken first.

 

[Josh lowe]

Just about anywhere. Its generic. I would try one from a car that is being broken first.

Okay mate ile try and get hold of one Thanks again

 

[Brigsy]

Hook it up to clip for diagnostics before you spend any money. See what codes are stored before guessing.

 

[andybond]

You have changed Man.

 

[Josh lowe]

What actually goes wrong with the n75 valve then does it stick open or something?

 

[Brigsy]

You have changed Man.

Always do the diagnostics first as changing parts that are not necessarily broke costs money. I dont think i would have ever fixed my clio without clip

 

[andybond]

Always do the diagnostics first. I dont think i wpuld have ever fixed my clio without clip

True , I have seen this on another car mind

 

[RanjD]

I had a very similar problem on my megane 225.

Diagnostics were pointing to a bad N75 Valve but it wasn't that , see :-

Megane - Running Problems - Fuel Pump ?

The problem was only at top of rev range to begin with and over time (as the pump became more worn) it spread lower & lower to the point where at 3000rpm at full throttle it would cut power off.

I would suspect a failing pump if the problem starts getting lower into the rev range. If you have a OBD2 scanner, check the fuel trims as it will help diagnose if it is this.

 

[Josh lowe]

Sorted eventually, turns out the actuator had seized with the wastegate fully shut hence the overboost!