New 25det owner Boost problems

[G2trop]

Car - factory turbo auto series 2 r33

I am having some issues with boost after going full throttle. What seems to be happening is after doing 1 or 2 pulls typically in 3rd gear it will basically stop boosting the boost gauge will go up to maybe 3 or 4 so psi (running stock boost) and have the same constant exhaust note (loud drone) regardless of what gear it is in. To fix this i usually pull over turn the car off and wait 5 seconds then it returns to normal no constant exhaust note and boosts how it should.

I think it might be worth noting the transmission Is pretty stuffed its the factory Auto gearbox and after warming up it will slip from 4th to 3rd with overdrive on and what sounds like 3rd slipping occasionally after heating up. I have changed the trans fluid and filter that seemed to prolong how long the gearbox took to slip. 

Any advice would be greatly appreciated i plan on manual swapping this car when i have the funds for a big box so if the trans is the issue it would be a relief.

 

[GTSBoy]

Put it on the dyno. Could be anything from ECU going into R&R, to AFM having a fault, boost solenoid cracking the sads. And a bunch of other things. These are so much easier to fault find if you can access the engine while it is under load (and faulting!).

[G2trop]

Thanks for the reply I thought it might be something to do with the ecu as well but I will look into the other faults