Lambda reading when rowing gears is off

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Lambda reading when rowing gears is off

Postby 88a5tq » Wed Apr 19, 2017 10:41 am

Logging while driving through several gears during a hard pull shows some pretty wonky lambda results that err on the rich side. Pulls in each gear separately results in satisfactory lambda readings. Who can relate and is this due to a brief vacuum on my direct port meth injection (using 2 solenoids)? Is this even a problem? I'll post an example log from yesterday later today.
Thanks guys
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Re: Lambda reading when rowing gears is off

Postby 88a5tq » Wed Apr 19, 2017 10:43 am

The first gear of the hard pull is normal and all consecutive gears appear rich. I have noticed the same happens if I pull only one gear, and engine brake after, that it goes rich also.
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Re: Lambda reading when rowing gears is off

Postby ChrisAudi80 » Wed Apr 19, 2017 10:43 pm

What happens is that when you let go of the gas pedal, you suddenly cut off air, but there is still a lot of fuel, so it goes real rich. Also because of the fuel film effect. However, lambda should then go totally lean because the residual fuel has been "sucked" through.
Do you see this? Or only rich? If so, you need to lower VE in the lowest kpa row.
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Re: Lambda reading when rowing gears is off

Postby 88a5tq » Thu Apr 20, 2017 6:21 am

Hmmmmm thanks for your reply. I couldn't find an acceptable log on I'll redo it today after work.

From memory, I think it stays rich for several seconds if I continue to engine braking, it slowly would climb to be lean. I'll try your suggestion as well, thanks!
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