R33 Rb25det - Cutting Out On Boost

[prawln]

Hey guys,

I recently put a RB25det engine into my partners R33 Rb25de car, Got it going etc etc. Im running the boost off the standard 5psi actuator. Its running ok but to be honest it doesnt feel like its really pulling. So ive just got a 10psi actuator and now when its boosting it cuts out at around 8psi when giving the car some stick.

In first gear it seems to be fine without cutting.

When i take it up hill it in 3rd gear it starts cutting at like 5 psi. I have taken videos that i have attached below.

Alittle about the car, Everything on it is standard but a pod filter. It has a RB25det fuel pump in it also.

I have put a fuel pressure gauge in also and the fuel pressure at idle is at around 40psi (alittle below) and when giving the car stick it gets up to around 60psi. Which to me seems fine with no issues there (im not very good with skylines, have only really work on my rx7)

Anyways i hope ive given good info about the issues.

Going up hill in 3rd gear, you can hear it cut/die then come back then cut/die again then come back.

Going down the street with foot flat. Car dies then when i pull foot off accel alittle it comes back.

Any help would be good!! Cheers guys!!

Edited September 8, 2010 by prawln

[prawln]

Also i have replaced all spark plugs but still seems to be doing it!

Ive been doing some searching and have seen some people talk about AFM cut? what is that and how can it be fixed?

Its running a stock ecu also and the AFM is the one that was used for the RB25DE engine but is the pink kind so thought it would be ok.. Do i need to buy a different AFM?

[Cupcake]

Stock fuel pump? AFM dirty? could also be a coilpack breaking down. CAS can be known to make a rb break down on boost.

[VRdrift]

have you used the DET wiring for this conversion? if so are you using the boost control solinoid?

[Luciano]

if he's not using the oem boost soleniod, the 25DE wiring loom is also fine for the DET conversion. Done it ourselves.

prawln: Is the 25DET a S1 or S2? AFM's between DE and DET motors are exactly the same, although the pink stickered AFM you have is for a series 2, and i don't think they are interchangable with S1.

We did the same conversion in my cousin's 33. At first it was running like absolute shit. All new parts installed - plugs, FMIC, pod, turbo back exhaust, 34 NEO turbo, walbro pump, aluminium radiator, new plugs, coils etc. He was running a little higher boost (around 8psi) and the car was cutting out exactly like in yours in the video. Lowered the boost down to 5psi and the problem wasnt so bad, but it was still running rough as guts.

tried everything we could, interchanging parts from another turbo 33, checking for boost leaks, consult, you name it.

anyhow, problem solver: Z32 ECU + NISTUNE + dyno tune! no more cuts, smooth through the revs, 12psi - gained 60something rwkw! and she f**kin flies.

not saying you need to run out and buy Nistune, but still, check for the obvious - any loose plumbing, BOV recirculation, try another ECU. You'll get there mate.