Lean Idle
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Lean Idle
When My Car Is At Idle And Is Warmed Up It Sometimes Begins To Drift In The Fueling Until The Point Where Its Running A 20:1 Afr The Seccond I Hit The Gas All Returns To Normal But I Can Also Hear The Enging Becomming A Little More Faint As If Its About To Die What Can I Do To Correct This?
Again This Is Only At Near Idle Conditions, On Hot Days, In A Warm Car (like In A Parking Lot) Driving Down The Road At Any Speed I Get A Perfict Afr
Again This Is Only At Near Idle Conditions, On Hot Days, In A Warm Car (like In A Parking Lot) Driving Down The Road At Any Speed I Get A Perfict Afr
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I'm having the same symptoms and it was suggested that the IAT was the problem but after loggin it, It wasn't. Still trying to resolve the issue but it seams that it's getting better after restarting my tuning from scratch. Now, it's only going to about 17 AFR instead of 19 AFR in my case.
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My Tune Is Good.. Hell It Was A Professional Tune By Tsp And Revised By Jeremy Formato...
This Is Just A "small" Glitch.. Im Wondering If It Would Be Due To The Giant Hole In My Throttle Blade Or Could It Be Just The Facts Of Life With A 240 Duration Cam In A 346
One Thought Is Mabye It Was Just A False Reading Do To Low Rpm Reversion With A Large Cam
This Is Just A "small" Glitch.. Im Wondering If It Would Be Due To The Giant Hole In My Throttle Blade Or Could It Be Just The Facts Of Life With A 240 Duration Cam In A 346
One Thought Is Mabye It Was Just A False Reading Do To Low Rpm Reversion With A Large Cam
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This seems more like the O2 sensor "going to sleep".
But the wideband ought not to, it has a big heater.
If the IAT is getting heat-soaked through the wall
of wherever it sits, and has negligible in-tube flow
to give it the right "signal" then this could push the
effective state-of-tune. If you extended the IAT
wires and put it out in free air and it got all better,
that would support the IAT theory. So would seeing
IAT reading creep at the same pace as AFR in the
logs. IF IAT stays put and AFR creeps than you can
discard this hypothesis.
But the wideband ought not to, it has a big heater.
If the IAT is getting heat-soaked through the wall
of wherever it sits, and has negligible in-tube flow
to give it the right "signal" then this could push the
effective state-of-tune. If you extended the IAT
wires and put it out in free air and it got all better,
that would support the IAT theory. So would seeing
IAT reading creep at the same pace as AFR in the
logs. IF IAT stays put and AFR creeps than you can
discard this hypothesis.
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In my case, it does it in open loop MAF tuning or close loop but when I do open loop VE tuning (SD mode) it doesn't happen. Basically, the only difference between Open loop MAF and open loop VE is the fact that I put the MAF fail frequency to 0 and the High RPM Disable under the Dynamic flow at 500 RPM instead of the stock 4000RPM. Since both open loop doesn't use STFT and LTFT the O2's should'nt affect it.
#12
FormerVendor
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Look at both your wideband and narrowbands to ensure they agree when the condition is present. The NBs should be looking very low, mV in the 2 digit area most likely. When WB sensors (more specifically, the cheaper common Bosch LSUs) begin to take a dump, they can look lean in places where they are not.
I am not saying this is your issue, but it's something to look at and it's something to keep in mind.
I am not saying this is your issue, but it's something to look at and it's something to keep in mind.