autotune for AE
Posted: Sun Apr 30, 2017 11:10 am
Why is there no autotune function for AE ?
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autotune for AE
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Re: autotune for AE
Posted: Thu May 04, 2017 9:37 am
Well that's clear
Re: autotune for AE
Posted: Thu May 04, 2017 12:17 pm
There are a couple significant technical challenges I can see with this.
1. The official response time of most wideband O2 sensors is 0.3 seconds. Three hundred milliseconds. I'm not sure if they define response time, as I've seen them take SOME action to an individual cylinder misfire. But the AE event may not be long enough for the wideband to actually get a good read.
2. You'd have to get the time delay between the combustion event and the exhaust traveling to the O2 sensor spot-on to make sure it has grabbed the right bit of data.
3. On a related note, if the O2 sensor was far enough downstream, the "slug" of rich or lean exhaust could have been diluted by the adjacent pulses before it reaches the cylinder.
4. You'd need to make sure the underlying VE table is spot-on.
1. The official response time of most wideband O2 sensors is 0.3 seconds. Three hundred milliseconds. I'm not sure if they define response time, as I've seen them take SOME action to an individual cylinder misfire. But the AE event may not be long enough for the wideband to actually get a good read.
2. You'd have to get the time delay between the combustion event and the exhaust traveling to the O2 sensor spot-on to make sure it has grabbed the right bit of data.
3. On a related note, if the O2 sensor was far enough downstream, the "slug" of rich or lean exhaust could have been diluted by the adjacent pulses before it reaches the cylinder.
4. You'd need to make sure the underlying VE table is spot-on.
Re: autotune for AE
Posted: Sat May 06, 2017 12:26 pm
Thanks Matt.Matt Cramer wrote:There are a couple significant technical challenges I can see with this.
1. The official response time of most wideband O2 sensors is 0.3 seconds. Three hundred milliseconds. I'm not sure if they define response time, as I've seen them take SOME action to an individual cylinder misfire. But the AE event may not be long enough for the wideband to actually get a good read.
2. You'd have to get the time delay between the combustion event and the exhaust traveling to the O2 sensor spot-on to make sure it has grabbed the right bit of data.
3. On a related note, if the O2 sensor was far enough downstream, the "slug" of rich or lean exhaust could have been diluted by the adjacent pulses before it reaches the cylinder.
4. You'd need to make sure the underlying VE table is spot-on.