Power Fc Knock - Again..

[nakuma]

I'm getting annoyed with this.

I've got the car tuned and retuned by Trent a few times now, but the knock levels keep spiking.

I'm trying to get the car ready for track but I'm scared if I drive it hard with the way it is, I'm going to do some serious damage.

I drive the car daily to work and keep it under 4 grand when doing so and get nothing above 20, but occasionally I feel like giving it a boot.

When I do, especially in 2nd and 3rd, I'll sometimes get readings of anywhere between 60-110 up and around the 5-6k mark.

The car feels fine, but I back off anyway.

I can't hear any pinning, but to be honest, I'm not 100% sure I know what I'm listening for.

On the dyno, the car is perfect. a healthy 200kw on the stock turbo (12psi) with std inj, std afm, nismo fuel pump etc.

I'm stumped, I've taken it back to Trent a few times, he takes out some timing, but the spiking still comes up occasionally when I open her up.

Am I getting false readings? Do I need a road tune? Is there something wrong internally? Is there a way to diagnose the issue?

I'm pretty sure I've gotten the lose cells on the tune covered because I've taken it back a few times.

Any help would be greatly appreciated.

Thanks.

[Don Dada]

So i'm assuming it does not do it on the dyno at all??

If you have the hc go to ign/inj in settings and minus a few degrees at a time and see if it still does it

[The Dan]

Trent is probably doing nothing wrong. The engine may not knock at all. 110 would definitely be audible.

The problem is also that you are pushing a stock turbo almost to it's full potential so you are generating a lot of hot air. This may cause knock spikes after a few sustained runs and it may not show up on the dyno

[R31Nismoid]

Take 1-2psi out of it. You might find the issue simply then goes away - reasons covered in post above me

[Guilt-Toy]

ask trent to put his knock sensor on the car and take it for a drive and listen to the engine, those knock sensors are designed to pickup knock on a completly standard setup, when you start changing the power outout boost revs and do mods to the car the knock sensors usually start to give false readings.

I don't know how willing trent will be to do this, i guess everything has its price for piece of mind. ie do not expect this service for free.

[DVS JEZ]

Get a mate to check what RPM the knock spike is at. Mine spikes when i change gears etc.

[nakuma]

Thanks guys, I'll get onto Trent for a road test when I've got some week days off.

I'm going to take your advice and drop a few PSI - only problem is, it's a manual turbotech boost controller and I've never fidled with it. Do I turn it clockwise or anti-clockwise? How much turn it for 1-2PSI?

[r33cruiser]

What condition are you plugs in?

I had the same problem, took it to my mechanic. He pulled out the plugs. They were in terrible condition. The ceramic on number 1 and 2 cylinder plugs were actually SHATTERED from the heat.

Replaced the plugs and the problem went away

[nakuma]

I turned the boost controller down a quarter of a turn gave it hell on the way to work today.

Maybe it was partly due to the hotter weather but she ran perfect - the knock levels never went about 21.

SAU saves the day again!