Hi guys, I was reading about 747 guys being able to set up such that the ecm goes open loop at idle only. Does this disable BLM correction? Is there any way for me to disable BLM correction at idle only w/ my 165 ecm? My choppy hydraulic cam causes the BLM's to max out at idle. Everything behaves properly above idle. The idle quality is fine but the ecm makes it as rich as it can until I cap the BLM. I have a 140 max BLM right now but the idle still is rich.

 

Anybody? I guess my only bet if I keep the MAF is to get the tune dialed in well with a wideband, then lock the BLM's to 128 or give the BLM's only a very small window of correction.

 

i am running OL and find that in winALDL there is no data being logged for correction. i thought i would still see my BLMS being posted but are all blank in datalog.

i have Tunercat and was told by them that i probably could run OL, only at idle, by setting the minimum speed to force OL idle in constants or minimum TPS to force OL idle. Here is where i am confused. i have both set to (3) and i believe i am still getting CL at idle when i am running a CL chip. i would expect when throttle closes 0% i should be OL and when car stationary I should be OL and closed loop everywhere else. But regardless CL is disabled today and WB shows too lean and that is not good either.

224/226 @ .05 and i have no richness at idle. in fact a bit lean.

what is your LSA?

 

Ronny, I will be changing cams soon as I do not know the specs on this one. It sounds and runs very similar to a 300/308 adv duration .484/.484 108 LSA cam I had in a previous engine. The idle is quite choppy but surprisingly doesn't hunt that much.

 

If you have all the calibration data, correct, then why not just run open loop all the time?. Then just use a closed loop chip, when and IF you need it.

 

The min TPS for open loop idle is set to 3? If so, that might be your problem right there. Raise that up. You're closed throttle might be a 4-8.

 

I am MAF and would thus rather not run open loop all of the time. Closed loop runs and drives perfect, so I really don't want to lose that. Since you can't directly change fueling in MAF, getting an open loop tune that is perfect across the board will involve time and fudging. Then once weather conditions change this tune won't be ideal anymore anyhow. I would be running a carb if I wanted a fixed calibration that didn't have any room to compensate for itself.

 

"See that's the kind of thinking you need to get away from my friend." - I forget but it was a pretty funny movie
Open loop doesn't mean it'll loose it's compensation abilities. It still compensates for things like coolant temp, IAT, baro, knock etc. it does NOT compensate for a bad tune. A bad tune is basically something that's running "well" from learning with the o2 sensor feedback (closed loop). A good tune runs better in open loop than closed loop. Very few engines actually run best with a 14.7 AFR so why run it that way? Even then, it isn't running a 14.7:1, it's above and below that... not exactly ideal for anything but emissions.
Also, open loop does NOT cause fudging, even with the 3rd gen MAF code.

 

"See that's the kind of thinking you need to get away from my friend." - I forget but it was a pretty funny movie
Open loop doesn't mean it'll loose it's compensation abilities. It still compensate for things like coolant temp, IAT, baro, knock etc. it does NOT compensate for a bad tune. A bad tune is basically something that's running "well" from learning with the o2 sensor feedback (closed loop). A good tune runs better in open loop than closed loop. Very few engines actually run best with a 14.7 AFR so why run it that way? Even then, it isn't running a 14.7:1, it's above and below that... not exactly ideal for anything but emissions.
Also, open loop does NOT cause fudging, even with the 3rd gen MAF code.