2003-04 Mach 1 Registry Owners Club - View Single Post - Thread for those of us who tune our own cars

Mach828 · 02-23-2015, 11:22 AM

I had been having hanging idle issues ever since I swapped to a smaller blower pulley. Did some reading and learned about adjusting the IAC duty cycle and dashpot settings. I just decreased the air flow requirements for IAC at drive and neutral until it datalogged ~45% DC, increased the decay rate in dashpot, and reduced the IAC multiplier based on ECT. Seems to have fixed my problem but I'll need to drive it more to be sure. Any other idle tricks? Seems like most people have problems with not getting enough air in to have a stable idle vs. having too much.

02-23-2015, 11:22 AM	#68
Mach828 Dark Knight Join Date: Nov 2009 Location: Albuquerque, NM Posts: 5,759	Re: Thread for those of us who tune our own cars I had been having hanging idle issues ever since I swapped to a smaller blower pulley. Did some reading and learned about adjusting the IAC duty cycle and dashpot settings. I just decreased the air flow requirements for IAC at drive and neutral until it datalogged ~45% DC, increased the decay rate in dashpot, and reduced the IAC multiplier based on ECT. Seems to have fixed my problem but I'll need to drive it more to be sure. Any other idle tricks? Seems like most people have problems with not getting enough air in to have a stable idle vs. having too much. __________________ Vortech V2 S-trim, E85, A2A Treadstone, Comp cams, built engine, full exhaust, built rear, built 4r70, more mods. Tuned by me with SCT Advantage