Short term BLM's never change?
08-18-2010, 10:14 PM
#4
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The short terms are not called "BLM"s...... they are called integrators, or "INT's". only the long term corrections are called block learn multipliers, or BLM's.
The short terms will stay locked at 128 as long as the PCM is in open loop. They only start to change when the PCM enters closed loop. The PCM will not go into closed loop until the coolant exceeds a minimum teperature (typically about 140*F) and the O2 sensors are hot and capable of working. If you have a defective O2 sensor, its not going to go into closed loop.
The short terms will stay locked at 128 as long as the PCM is in open loop. They only start to change when the PCM enters closed loop. The PCM will not go into closed loop until the coolant exceeds a minimum teperature (typically about 140*F) and the O2 sensors are hot and capable of working. If you have a defective O2 sensor, its not going to go into closed loop.
08-18-2010, 10:29 PM
#5
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First, if it matters, my tune was from MadZ28.com based on my cam/heads, then I've been tweaking the fuel from there.
Well in DataMaster, it is reading as Closed Loop and the short terms are locked at 128. When I initially load a new tune the Long Terms are all at 128, and they eventually change after I drive the car for a while.
Fuel cell 16 (idle I believe) has never changed from 128 long or short, no matter how long it runs on a new tune.
My wideband also reads lean at idle, around 17-18 as well as cruising, (ie. highway) around 15-16, even with the long terms close or at 128. However, once the gas is applied a little more, it shoots up to a more normal 14 or so a/f (still tweaking the fuel to get closer to 14.7 when doing part throttle)
Well in DataMaster, it is reading as Closed Loop and the short terms are locked at 128. When I initially load a new tune the Long Terms are all at 128, and they eventually change after I drive the car for a while.
Fuel cell 16 (idle I believe) has never changed from 128 long or short, no matter how long it runs on a new tune.
My wideband also reads lean at idle, around 17-18 as well as cruising, (ie. highway) around 15-16, even with the long terms close or at 128. However, once the gas is applied a little more, it shoots up to a more normal 14 or so a/f (still tweaking the fuel to get closer to 14.7 when doing part throttle)
Last edited by kgkern01; 08-18-2010 at 10:46 PM.
08-18-2010, 10:34 PM
#6
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....Also, in TunerCats, in the switch table, there is an option: "Data Stream Fuel Enable" which is un-checked. What does this switch mean? I cannot find any info in the TunerCat help or searching online?
08-19-2010, 12:21 AM
#7
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Think I found the problem, the #4 injector plug had came loose. Unplugged the PCM fuse for 2 min, then started it back up, and then DataMaster started showing the short terms. This should make tuning the fuel a little easier now, lol.
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