Voltage Affect Idle?

[AngryRB]

Trying to figure out why the car is idling so rough, the fuel pressure guage seems to fluctuate, at idle its between 42-43, holding the throttle open on 2000rpm it will hold on 42psi, release the throttle and the guage rises for a second on 46psi and the engine tries to stall, but the recovers and the pressure is back at 42-43psi.

just need to know if that sounds normal....

and if the voltage at the pump is fluctuating or getting too high could that affect idle quality or does the computer compensate for different voltage.

Another thing, does changing the setup to a twin scroll 6boost and turbo affect the engine breathing enough to create a rough idle?

Edited June 22, 2013 by AngryRB

[AngryRB]

may have made some progress here, in the power fc theres a function for "injector Correction" that was set at 1.000

raising this to 1.500 and also raising the idle to 1000rpm , the engine sounds almost normal and wont try to stall, can anyone make sense of this?

[DVS JEZ]

By raising to 1.500 u have added fuel. Did this fix the issue?

Test fuel pressure and get the tune checked.

Check for vacuum/airleaks too

[AngryRB]

yes its smoothed the idle out and it now doesn't stall on me anymore, seems to idle at 1200rpm when I declutch quickly instead of wanting to stall too..

the fuel pressure has some down a little and holds firm and only increasing with a flick of the throttle, so funny how much its changed

will have it tuned properly in a few weeks, its interesting how a change to a 6boost manifold and a GT30 instead of a GTX30 has required more fuel, ( assuming its not a vacuum leak) .

[DVS JEZ]

If u have changed the intake pipe setup for the afm position this can happen. It may be reversion through the afm.

What ecu and afm?

[AngryRB]

Its a Power Fc with a Z32,

Do you think having a 4inch intake pipe and a Z32 would cause some false readings due to volume and speed of gas flow thru the two different sized pipes.

Edited June 23, 2013 by AngryRB