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**Gregski** · 03-08-2020, 03:25 PM

Idle Tuning - Idle Fuel Trims

time once again to add more Channels, now don't let these throw you off they do not mean there is a fourth component to our Holy trinity, ha ha these are bundled into the Airflow third

by this time we've all heard of Fuel Trims, more specifically the Short Term Fuel Trims aka STFTs and the Long Term Fuel Trims aka LTFTs, but did you know there is a whole other set of Fuel Trims?

We have the Short Term Idle Trims which HP Tuners calls Idle Adapt (STIT) and for some reason they don't come separate for In Park and In Gear (oh well) and Long Term Idle Trims (LTITs) for both LTIT PN/ACoff and LTIT Gear/ACoff.

stay with me now, it's going to all fall into place shortly

So look at the LTIT PN/ACoff channel it is removing 2 lb/hr (so 42 Base PN minus 2 LTIT PN equals 40 Desired) there's our smoking gun!

Important Take Away: being only 1 lb/h off by either the Short or Long Term Fuel Trims is super awesome, if that's what you are seeing, go have a beer, you're done, ha ha. I am quite happy being 2 lb/h off for each one of those, but keep reading we are about to learn that up to 4 lb/h is still good.

03-08-2020, 03:25 PM	#355
Gregski Post Whore Join Date: Aug 2014 Location: Sacramento, CA Posts: 10,810	Re: HP Tuners Tutorials - Idle Tuning Idle Tuning - Idle Fuel Trims time once again to add more Channels, now don't let these throw you off they do not mean there is a fourth component to our Holy trinity, ha ha these are bundled into the Airflow third by this time we've all heard of Fuel Trims, more specifically the Short Term Fuel Trims aka STFTs and the Long Term Fuel Trims aka LTFTs, but did you know there is a whole other set of Fuel Trims? We have the Short Term Idle Trims which HP Tuners calls Idle Adapt (STIT) and for some reason they don't come separate for In Park and In Gear (oh well) and Long Term Idle Trims (LTITs) for both LTIT PN/ACoff and LTIT Gear/ACoff. stay with me now, it's going to all fall into place shortly So look at the LTIT PN/ACoff channel it is removing 2 lb/hr (so 42 Base PN minus 2 LTIT PN equals 40 Desired) there's our smoking gun! Important Take Away: being only 1 lb/h off by either the Short or Long Term Fuel Trims is super awesome, if that's what you are seeing, go have a beer, you're done, ha ha. I am quite happy being 2 lb/h off for each one of those, but keep reading we are about to learn that up to 4 lb/h is still good. Attached Images Last edited by Gregski; 03-09-2020 at 12:28 PM.