Join Date: Mar 2006
Location: Cenla, Louisiana
I wil address your idle fluctuation. The t5 trans has a clutch switch and neutral safety switch to tell the a9l computer when it is in neutral or drive. The computer switches from idle strategy to drive strategy depending on the two mentioned switch positions. If you have the neutral safety switch diconnected when switching over to the c4 then the computer is going to adjust the idle air and timing for drive strategy because it has no way of knowing you have the c4 in park or neutral. When you push in the clutch the computer see that switch change and changes to neutral idle strategy. Make sense? Do you have a neutral safery switch on the c4?
'91 Ranger, 306, 270HR14, Tri-y, RamAir, T5, 3.73, Aeromotive Sys, QH, LM2, Tunerview II, A9L, BE & EA
'89 Mustang coupe, 5.0, AOD, HO cam, 70mm Turbo, 60lb inj, 340lph, 3.27, QH, LC-1, A9P, Tunerview II
'98 Ranger 2WD 5.0, GT40, HO cam, 4R70W, 3.73, QH, SLL4