Vz v6 supercharged fuel problem help

[Spudrageous]

It'd be awesome if someone can answer this
I have some sort of fuel problem. I bought a scan tool to try figure it out. It was showing that my long term fuel trim is constantly at -12.5% for bank 1 and -10.9% for bank 2 right through the whole rev range and cold start up. Short term fuel trim is fine and O2 sensors are fine. Not throwing any DTC's.
I have got 450cc injectors but still using the stock fuel pump. Charger runs at max 9psi.
My ute occasionally has a bad start. Fires up straight away but at very low revs, almost stalling, then comes up to normal. This happened ever since it was tuned. The other day after a drive it wouldn't start at all. I turned the key off and tried again and started up perfectly. The car also has a slightly rough idle and shakes the car a bit.
So my questions. Can my stock pump not handle extra flow, Or is it just starting to fail? Is my pressure regulator failing? Or is it something else?
Yet to have my fuel rail pressure tested
Any help is appreciated

 

[SVTato]

I would be getting after market pump and regulator cause if it's not getting fuel it will start to lean out and that's not good number one cause of detonation and pinging....


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[RiCeY]

Long term trims indicate the car is running rich as its pulling fuel out. This would also explain hard starting and rough running.

 

[Spudrageous]

Yeah I actually thought it could be an over pressurising problem as both banks are trying to reduce fuel so the pump must be ok and therefore it points to a regulator problem but I am no expert. If i have to replace it i will definitely go high performance. Could it possibly be the fuel map that is used in my tune file? Trying to get a hold of the tuners to get it looked at.

 

[richardpalinkas]

Funny enough I have a supercharged sv6. Bad start for me too. The way it's tuned is because the ecu is tricked to have smaller injectors, so that's why it thinks fuel trims are out of whack.

 

[RiCeY]

Fuel trims work off the 02 sensors so injector size should be irrelevant as it measures the fuel content in the exhaust emissions.

Id say the issue is needing a lot of fuel on boost but normal amount off. No idea on the tuning capabilities of the V6 ECU but the fuel maps should be able to be adjusted for varying revs.

Id have a chat to the tuner and see what they think.