FAST EZ-EFI tuning advice needed
This spring I ventured into the brave new world of EFI, and installed a FAST EZ-EFI 2.0 system on my Camaro. I also installed a new Tanks, Inc. fuel tank and an in-tank fuel pump. After diagnosing and replacing a bad ECU module, Iíve been driving the car for the past few weeks and allowing the FAST system to learn. Iím pretty happy with it Ė throttle response is outstanding, cold start is much easier, and the fuel economy has improved. My car doesnít have gauges, so the handheld monitorís ability to display coolant temperature and battery voltage is also a plus.
Iíve left all of the FAST AFR settings at the factory default values and given the computer some time to learn. As Iíve become more familiar with how the system is operating, Iíve noticed a few gremlins that Iíd like to try and correct by tuning the system. Trouble is Ė I donít know where to start.
Hereís what Iíve noticed so far:
The IAC calibration is a little tough to get right. The indicator is usually to the left of the preferred target when the car is idling in Park, and to the right of the target when the car is in gear.
The system seems to hunt for the correct idle speed for quite a while before finally settling down at the idle speed Iíve selected (870 RPM). This problem occurs frequently when the car is restarted after itís come up to full operating temperature.
Iíve also noticed a small off-idle stumble when the car is up to full temperature. The system has an Accel Fuel adjustment available, but I havenít messed with it yet.
Iím hoping there are a few folks on this site who have ventured down this path already, and can give me some advice to tune the system. Thanks!
69 RS, Hugger orange/black, Deluxe interior, Sony AM/FM/XM/CD, PS & PB. 355, forged pistons, Eagle rods, balanced, Iron Eagles, 9.4:1 CR, .038 quench, XR270HR Cam, Z28 intake, FAST-EZ EFI 2.0, Thorley Tri-Ys, TCI 700R4, 2400 stall, 3.42 posi