Hi everyone,
I have run into a problem today when getting my car tuned. Car is a Nissan Skyline R33-25T Stright Six Turbo. Reason I was getting my car tuned was that I have upgraded to a 300ZX AFM from the Skyline one. And installed a smaller exhaust housing for my Garret GT30 turbo. Everything else being the same.
I am running a Tial wastegate.
On the dyno run I loose power when the car reachs around 0.6~0.7 bar boost and anywhere around 4000~5000 rpm. It sounds like its mis-firing and gets all rich with black smoke coming out the tail pipe. So during the day I replaced the plugs, at first we gapped the plugs to .028 then .020 thou without any luck, then we tried replacing the coil packs... no luck. After I got home I borrow from friends car a working "Igniter / Amperifer" that sits on top of the valley cover and tried that in my car without luck. Because I can rev the car on the road all the way to redline as long as I keep the boost low.... E.g 0.2~0.3 Bars. So then I suspect its the Wastegate or the boost control system.
FYI - I am running a Apexi PowerFC with the boost control kit. And a Tial wastegate
So I changed boost settings on the PowerFC without any effect to the problem, I then disconnected the blue silcon hose from the boost control valve and it made no difference too. I then tried using another boost control valve from another car that I know its working .... no luck either. So now I suspect its the wastegate that is not working, since I don't have much experience with wastegates can someone tell me what to check for and how? Like procedure of taking it apart if it requires servicing.? Attached is a photo of the setup. Yellow hose goes to pipes after the turbo. And Blue hose goes to the Boost control valve.
Cheers
Felix