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kamilymak
03-06-2016, 11:12 PM
Hey guys new to SR need some advice, i did a lot of reading still cant figure out this problem:

I am severely lacking power when accelerating here are three different scenarios of what occurs under acceleration:

1. While accelerating boost gauge shows turbo spooling easily but power is not there at all.

2. While accelerating boost gauge will hop for split seconds and the car bogs under boost, then randomly the car will get the power and lose it again

3. While accelerating all is good spools hard and pulls like it should!

Theres days where it goes from complete shit with no power for half the day then randomly after work on my way home it pulls with no issues.

The car used to idle high with the same issues and a buddy messed with the CAS and now it idles fine but the boost issue is still there.

Here is what i did to try and fix it:
- Swapped all coil packs/harness with a buddies
- Swapped BOV as previous one was leaking
- NGK spark plugs
- Checked for vacuum leak (Vacuum is at 15 at idle but when in gear with no throttle around 21)

Car is running on a stock ECU, SAFC2 (factory settings), SOHC KA MAF, car has a couple mods and runs very rich, the fuel smell is very strong. Vacuum is at 15 when idling but when in gear with no throttle around 21. Boost is at 10psi.

MOD LIST:
- T28 turbo
- Greddy FMIC
- Koyo Radiator
- Greddy PROFEC B Spec 2 boost controller
- Blitz BOW
- Blitz turbo timer
- Apexi SAFC 2 (factory settings)
- Full straight pipe to muffler

I know some of the stuff in the mod list might not matter or the mods dont even matter in general but i through it in there just in case it does. The car also has a python alarm/remote start system, which i doubt matter but again just in case.

jedi03
03-07-2016, 10:13 AM
Try a new 300zx tt fuel filter...could be fuel pump too...

ultimateirving
03-07-2016, 03:32 PM
First I would remove the safc. To make sure it is not impacting anything but also cuz they aren't useful for the mods you have listed.
You should be able to run that t28 at 11-12psi with no tune/problems(given everything else is working properly)

Check the Tps, and knock sensor. The tps should be at ~.45v closed, and under 5v wide open. While moving from closed to open the voltage should change very linearly and not jump around.

The knock sensor should be connected and tight against the block

kamilymak
03-07-2016, 11:16 PM
I will definitely look into those thank you guys!

hanzbrady
03-08-2016, 07:04 AM
Check your base timing.

kamilymak
03-13-2016, 01:40 PM
Bump. Any other suggestions? I will be trying some of the advice today more advice is welcome!

Thank you

mando240
03-16-2016, 03:32 PM
Bump. Any other suggestions? I will be trying some of the advice today more advice is welcome!

Thank you

Start with the timing like previously stated, I'm assuming stock injectors? check for leaky injectors. What is your fuel pressure set to?

I would also disconnect the Safc or remove fuel with it, maybe you have the wrong in/out if its in factory setting. If you don't know how to use an Afc, don't touch it! With the mods listed, unless you have bigger injectors, your stock ecu should run that setup perfectly fine.

It doesn't hurt to check the tps and maf as well. Do a compression test.