Misfire over 6000 rpm

[Paul V]

Have a misfire over 6000rpm, its as if it hit the limiter, had this before and was the coil pack on its way out but it is only 5 months old so hoping its not that again. I replaced the leads and plugs at the same time so everything is fairly new, it's also had new clutch recently and I cleaned the earth when doing that.

Thinking I'll need to get it on the pc and check the lambdas. I might try a new set of plugs too.

It often did it when running 95 octane but now running optimax and it's still doing it.

It's not a huge issue as don't spend much time over 6k anyway but nice to be able to if you want.

[tvr5000]

Had the issue with mine, and it only happened when I put optimax in it. Other fuel was better but still happened every now and again. Eventually put down to faulty lamba. After that it ran on anything up to the limiter very smoothly.

[yzf1070]

I would be surprised if it were the lambda's as they are not wide band. They have little to no function beyond 4000rpm as the ECU runs open loop on preconfigured settings based around MAP, RPM and throttle position. Especially if you are WOT the lambda's are ignored. At least thats my understanding..... I would suggest you check that your throttle body spindles are not worn which leads to rougue/erratic throttle position values being sent to the ECU.......anyone else correct or add to this?!?

[s6boy]

What temp was your oil and water at the time?
I had the same the other VERY cold weekend, tooled around Cambridge oil up to 65 degrees then onto M11 for 10 mins and temperature fell to 47 degrees, when I put my foot down in 2'nd coming off a roundabout it felt like I'd hit a brick wall the limiter was so violent, as this has happened before when I needed a new coil pack I wasn't too worried changed up to 3rd and away I went no problems then or since. Spoke to my garage about it and it was mentioned that maybe the car has a safe mode which prevents damage to the engine if not at correct temperature. Maybe someone on here can confirm or deny this?

[saulk]

I also seem to get this when using Optimax. Running on ultimate or Esso Super she runs fine.