open loop vs closed loop?

[JUSTA3.8V6]

i just got my turbotweaks chip sent to me and i was just wondering the difference between open loop and closed loop idle? are there any benefits to open loop?

 

[TurboDave]

i just got my turbotweaks chip sent to me and i was just wondering the difference between open loop and closed loop idle? are there any benefits to open loop?

Open loop idle in general is a smoother idle simply because it's running richer (in the 13-13.5 as apposed to the stoiceometric 14.7 of closed loop)

Closed loop used input from the O2 sensor to maintain 14.7:1 air fuel ratio.

Open loop does not use the O2 information but rather uses static tables in the chip, hence the richer tendancies.

 

[norbs]

Yes, reduced gas mileage, and better throttle response and increased emssions in open loop.