Open Loop....
Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
There are some that do run in open loop all the time though. I was just curious because my throttle response seems to be so much better when it is in open rather than closed loop. Also the idle is better.
Race Director
Joined: Apr 2000
Posts: 15,344
Likes: 4,008
From: Texas
With a big cam you can clean up the idle so that it doesn't smell. It's also easier to address cam surge at low rpms.
At WOT it really doesn't matter since the PCM ignores the O2 sensors anyway...well...if the fuel trims were >0% then it will add some amount of fuel to the base Power Enrichment value but you'd only notice it on a dyno or if you were consistent within a few hundredths at the track. Basically at WOT you're in Open Loop.
If you get it wrong with open loop, you can seriously fubar the engine, the cats, etc.
At WOT it really doesn't matter since the PCM ignores the O2 sensors anyway...well...if the fuel trims were >0% then it will add some amount of fuel to the base Power Enrichment value but you'd only notice it on a dyno or if you were consistent within a few hundredths at the track. Basically at WOT you're in Open Loop.
If you get it wrong with open loop, you can seriously fubar the engine, the cats, etc.
