# any of you OBD II guys run open loop all the time?

**URL:** <https://forums.speedlife.net/t/any-of-you-obd-ii-guys-run-open-loop-all-the-time/201616>\
**Category:** PittSpeed Automotive\
**Created:** [January 23, 2009, 5:19pm UTC](https://forums.speedlife.net/t/any-of-you-obd-ii-guys-run-open-loop-all-the-time/201616 "2009-01-23T17:19:54Z")\
**Posts on this page:** 1\
**Showing post:** 13

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**Author:** ![SK360](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/sk360/32/5933_2.png) [@SK360](https://forums.speedlife.net/u/SK360)\
**Post date:** [January 25, 2009, 9:39am UTC](https://forums.speedlife.net/t/any-of-you-obd-ii-guys-run-open-loop-all-the-time/201616/13 "2009-01-25T09:39:11Z")

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> [@Ron paul schools McCain at debate last night](https://forums.speedlife.net/t/ron-paul-schools-mccain-at-debate-last-night/39446/6):
>
> see that is where the 3800 is very different from the LSx motors. It will carry Negative and positive into PE. the Trims are acutally based off the MAF, and all the changes to the MAF effect the Trims. My LTFT’s lock in at 0.0 every single time when i enter PE, and all the other cars that i have tuned lock in too. It takes ALOT of dialing in the MAF to achieve the trims where you want them. There are alot of factors that play a part in the trims. I can have perfect trims one day, the weather changes and they are shit the next. I have done alot of MAF tuning over and over to get them right. My crusing trims are +/- 3 and yes they do bounce around depending on TPS/MAF

If the LTFT’s lock to 0.0, then it is not carrying trims over, cause theres no way your running 0.0 LTFT’s all the time…

The trims are based off of the MAF in every car tho, because the fueling is based off of the MAF, and the front O2’s give a reading to the PCM and the PCM adjusts fueling via the trims for that MAF cell

That is what the trims and MAF is there for tho, is to adjust to the weather and altitude… If I wanted to retune my car every time I ran it at the track, I would run OLSD 😃

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