DP Fix alike solution for ST post turbo O2s?

Levanime

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Supporting Vendor
Nov 5, 2016
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NorCal
Hey,

probably this idea was discussed earlier, but could not find any thread about it,

As we know if you place both O2 on ST in DP, DME starts acting weird when it sees same readings,

why would not DP Fix alike solution work in this case?
im not sure how heavily DP Fix changes signal from "source" to "result"
but, would not keeping O2 readings "ALMOST" same, just slightly different work?

or link me the thread it was discussed in :)

thanks!
 
Last edited:

doublespaces

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Oct 18, 2016
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Hey,

probably this idea was discussed earlier, but could not find any thread about it,

As we know if you place both O2 on ST in DP, DME starts acting weird when it sees same readings,

why would not DP Fix alike solution work in this case?
im not sure how heavily DP Fix changes signal from "source" to "result"
but, would not keeping O2 readings "ALMOST" same, just slightly different work?

or link me the thread it was discussed in :)

thanks!

This was discussed, but I can't remember the reasoning. @jyamona @V8bait @Twisted Tuning @WedgePerformance @[email protected]

One or all of these guys know.
 

Levanime

Lurker
Supporting Vendor
Nov 5, 2016
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NorCal
thanks, hope they will reply,
i guess main thing is that the "other" signal should be varying, if it keeps to be different in same direction it will cause leaning or enriching AFR accordingly
 

jyamona

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Nov 7, 2016
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The DME has a cylinder individual lambda control (CILC) process that it runs periodically to keep the AFR in each cylinder as equal as possible. It does this by richening / leaning out one cylinder's injector and monitoring the effect on that bank's AFR reading. When both lambdas are post-turbo in the same pipe, each bank sees the corresponding change and the DME realizes something is amiss.

Additionally, there are a few other checks in place like time-lag models for when the exhaust pulses should reach each lambda sensor, etc.
 

doublespaces

General of the Army
Oct 18, 2016
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The DME has a cylinder individual lambda control (CILC) process that it runs periodically to keep the AFR in each cylinder as equal as possible. It does this by richening / leaning out one cylinder's injector and monitoring the effect on that bank's AFR reading. When both lambdas are post-turbo in the same pipe, each bank sees the corresponding change and the DME realizes something is amiss.

Additionally, there are a few other checks in place like time-lag models for when the exhaust pulses should reach each lambda sensor, etc.

And your solution involves neutering those checks or converting them to a single bank?