So I brought a project v4 about a year ago coz it was cheap and its had some chatter when the gate opens and it becomes sluggish
The gate sounds like its opening then shutting as soon as it opens continuously like a knocking
It boosts fine and surges/vents as it should till the gate opens then tractors along but still holds 10 - 12psi with a 14psi spring in and will still vent or surge as normal
Throws a CEL when crusing in 5th but goes away when the cars turns off and has a lack of power/pick up
Car idles high now and then to about 1500rpm but goes away after a bit possibly a vac leak - idles at -19/20psi could be the dent in the intercooler
Bogs on take off in first and shudders in gears in low RPM but suspect the knocking and shuddering in the diff has something to with it or the clutch hasn't been lined up properly but there's no shake on the pedal
I did have quite bad overheating issues so replaced the thermostat and hoses with new ones and swapped in a spare factory radiator with one fan due to the FMIC but runs cooler than before
Still uses a little water though
Noticed the rear seals and rocker gaskets have been RTV'd on

What the car came with..

VF30 with cracked rear housing
V7 decat downpipe
HKS mushroom pod filter
Larger A/M SS up pipe
Stock headers
Orange Nissan AFM
Yellow injectors
1S ECU
FMIC
38 gate on the elbow

The order in which I fcuked with related tings..

Welded the crack and the internal shut and redirected the vac line to the external as they were both opening and unplumbed.. TF?
Replaced hacked up GReddy BOV for a good working Racepro blaster
Bypassed the factory 3 port
Tried using a turbosmart boost tap with and without the 3 port bypassed on different settings
Swapped the 38 with 2 other known working ones - 12 and 14 psi springs using the tap as well
Changed plugs
Plumbed new 2mm vac lines correctly
Swapped the VF30 for a 23
Changed coil and leads
Moved knock sensor back onto the block
New restrictor pill as was missing - in line from turbo
Swapped in a 2009 STI fuel pump
Replaced the oil feed line with SS braid and fittings to suit as the line split and pumped the oil everywhere
New charge pipe

I made a new engine harness copying the original as it had exposed wires and was rugged
The carbon canister is missing the 1 inch piece of hose from the steel tube to the canister IDK bout that but I'm removing it
Also noticed the block is a MY99 with v4 heads and the box is from an MY99 too and the diff is still a 4.44 r160

I'll be doing the following on the weekend..

New plugs and knock sensor
Changing the diff with another R160
Cylinder 4 mod for peace of mind with water usage and earlier overheating
Scan for codes after throwing the CEL
Compression test

If I can't sort the issues in the next few weeks then I'll bin this setup and swap in a built 257/link/locked 6 speed/custom subframe and lock set up from the BP

I've spent months trawling through forums and threads but haven't found anything definitive
Any help or ideas are much appreciated

Cheers

 

you may well see more issues if you undertake that "cooling mod"..........

 

Do tell more.. Whats the cons to doing it?

 

various threads on here, follow the links........

https://www.scoobynet.com/general-te...olant-mod.html