Megane rs 250 missfire :(

I have noticed the same some times. I think it is normal.....

 

I've noticed a similar thing. With mine I usually have to lay off the throttle and come back on again to get it to stop. It sounds like its completely riching out, perhaps missing in all 4 with no power being produced. It did it to such an extent once that it never recovered from it, the car was missing in all cylinders and chucking a cloud of un-burnt fuel out of the back. A restart fixed it and its never happened again. The fuel I was using was tesco ultimate, I use shell now and have no issues. I've always suspected the bluefin map isn't great so intend to get it changed at some point. What surprised me was that no fault codes ever came up!

Some codes I get every now and again are the anti pollution and check injection. The actual fault code says unexpected levels of boost. I guess there could be a coil pack or spark plug issue at play. I also have my eye on changing the crank sensor.

 

Yeah that's the problem with these things, you can be chasing a fault for ages and it can become a real money pit. So many different sensors and components. I looked briefly into coils a few weeks ago and saw that is was around £40 for 4, I may misread this as it does seem quite cheap. They were likely not official ones

 

Ebay has NGK ones for £20 each.... I would try those personally, save a few quid!

 

Especially on plugs supposedly, Paul at RS mentioned they were pretty fussy if they were not 100% spot on.

 

Sounds normal to me, mine does it time to time when you the limiter right, mine is mapped thou.

 

Have you got traction off completely when you are doing this ?

 

Had this happen once or twice with my 265 also, like you said when you are properly giving it the welly...

 

I've noticed recently that the misfire counter (torque app) on mine also increases during a drive (is zero when starting the car). They seem to happen on overrun though, and I haven't noticed any driveability issues - don't know if that's normal? (car is mapped)

 

It was one reason for me to remove the tuning box out of my car, as it felt like a missfire time to time. Now in stock condition it feels much smoother.

 

Coil pack/s likely issue & ngk plugs are fine
Should be silky smooth at all times, anyone tell you anything else is kidding. Mine has no shudder judder miss or stutter on idle,part or full throttle.

 

I had a post similar to this and people told me it was the cold limiter I've have had this issue twice too but not for a good few months since I've been using Shell V-Power, and the cars also been mapped since then too

 

This is misfire on the limiter, not the limiter coming in earlier

 

Doesnt more fuel get chucked into the cylinder on the limiter to cool it down?

 

As suggest fill her up with Shell V-Power and report back. Whats the milage on your car?

 

Mines suffering from the same bud. Maybe a second of misfire once you've changed up on full boost. Car does nothing and then comes back

I'm on 61k with a map 290bhp

 

Random idea... Try it with traction control switched off... I'm getting strange issue that's similar on mk2 r26 but never happens with TC off.

 

Mine does it with T/C off

 

Guy I've spoken to on Facebook says his was doing this too and got worse and worse.
He had a compression check and got a read back of 150,150,100,40.
Apparently then he blew his crankcase Seal and fudged a piston due to the low compression.

Abit worrying if this is linked but I don't have a clue

 

Those engines are called as bulletproof, as much as i know, especially on stock condition. I dont think that everyone engines are blowing now as one guy had some compression check and faulty readings. Sometimes reading all the forum threads and replys on the internet it feels like your car is fckd up in every way, but actually it isnt that bad at all
Is it happening when you hit the rev limiter or is it doing that even if you change the gear on the right rev?

 

Just read this. Don't know if I am worried or relieved.... I get this now and again, but usually with TC Off.

The only time I've experienced this is when properly going for it and catching the limiter in 1st into 2nd. I always lift off and it's fine, I've never had the balls to keep my foot planted with the noise it makes! Definitely a complete loss in power though.

Always run on V-Power Nitro+ or Trsco Momentum 99 - Standard car with ITG panel and mid box delete.

 

Seems a fair few of us experience this then.

 

Are all these cars mapped? I was always thinking it was my map

 

Negative. Mine is standard with ITG panel and mid box delete.

 

If it's that bad it could be a boost leak maybe? Speculating without seeing or hearing the vehicle. Hope you get it sorted mate.

 

I experienced this again today, but catching the limiter in second changing into 3rd.