R33 Surging Problem?

[iBd14U]

Hey guys and girls,

Im wondering if anybody knows anything about the weird surging problem i get in my car and if anyone knows how to fix it. When coming on boost wif the accelerator full to the ground the car just keeps on surging and it seems Im losing heaps of power. The car has not always done this. But has started recent. Some say its the AFM but Im not sure. I've got a Mine's ECU in atm and still seems to be doing it. Any clues? Its a Series 2 R33. Thanx!

[knore]

It could possibly be the mines ECU itself,

some things to rule out:

Fuel quality and fuel filter

Exhuast back pressure - What exhaust u got and how much boost are you running?

Spark plugs and their gap

Coil packs

Piping/pressure leaks

just a few..

[Cubes]

I would say from experience its either leaning out then slightly pinging causing the ecu to drop massive amounts of timing or its just simply detonating in turn the ecu will richen it right up and pull heaps of timing.

My RB30DET does it as it comes on to boost with the stock rb20det ecu. AFR's when it comes on to boost creep up to the low 13's causing maybe slight detonation that the knock sensors pick up in turn it drops the ignition timing from 22degree's to 8 degree's and dumps a heap of fuel in. The RB20DET base map isn't designed for the rb30det in my case.

So I've wired the wastegate all the way open and the AFR's are fine.

With the wastegate wired open the exhaust is 2x louder easy.. Much more drony and actually sounds quite tough.

[iBd14U]

I only just got the Mine's ECU put in as a test. Cause it seemed on the old stock ECU the car would spit and cough alot more then it does now. Im not to sure if its the AFM as people say that when modifying your car some where in the process you'll need a a bigger AFM such as the AFM from the Z32 twin turbo. Im not sure if this would fix the problem. Possible?