HELP.... Power to 5000RPM Power Loss

[-Joel-]

I am getting a problem.

When full boost develops nothing really happens Most of the time until around 5000rpm then it takes off.

Please read the Attached File.. It has a list of what i've done and tried since the problem started.

Please Help.. <bangs head on bonnet>

It has made it very gutless in traffic like when short shifting from first then giving second full boost and pulling away from around 3000rpm.

COULD IT BE MY AFM?!?! It has caused problems before and when on idle and the car is cold if i ever so slight touch the throttle it will causes the car to run rough and the rev's will drop.

On the road it makes it hard to cruise on 60 km/h until it warms up.

I removed the AFM Mesh and it almost removed the problem but it can still be felt only every so slightly and only every now and again..

On std boost the problem is not there.

[Gonthrax]

Well, the only thing I can think of is that for some strange reason, your ECU is retarding your timing. Now why it would be doing that I donno. I would say that it detects ping but you shouldn't be pinging on the 101 RON and you said you didn't hear any... Perhaps the AFM does have somthing to do with it... I wish I could help ya out but I'm really at a loss. So my .02 is retarded timing. Or retarded ECU, or one on account of the other

Lemme know what you find when you get it sorted.

[-Joel-]

What actually happened is that I have a fuel pressure bleed kit on her to help lean the mixtures out a little as the skylines run so rich.

Anyway with the std fuel pump it would supply enough fuel in the mid no worries and start to lean out a little towards the top end but it was still running rich so with the fuel pressure bleed the fuel pressure lean out top, I was able to get good AF's through out the rev range.

THEN..

I fitted the Bosh 910 fuel pump and it was able to supple heaps of fuel every where so now it is either have good af's in the mid and run a little rich up top and loose a bit of top end or have good top end and run a little lean in the middle which caused the loss of power until 5000rpm.

I've wound the screw in a little on the fuel pressure bleed and i have lost a little bit of top end but at the moment it is still better than having no fuel pressure bleed and running 10:1 at the top end as that is what it was without the fuel pressure bleed.

So now I have the good kick again and no pinging it doesn't like to flick to the 7000rpm as much now it tends to start feeling like you have to change gear at around 6200-6500rpm.