EGR explained (and awesome video resource for 4D56 technical questions)
- Thread starter noah_crab
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- egr removal resource tuning
suburbanite
New Member
Why do so many Delica L300 users delete theirs then? And why does he say the 4D56 that he owns never came stock with one?
Early installations of the 4D56 did not have an EGR valve installed (that looks like an early non-turbo Pajero).
There's a couple things about that video... firstly the two benefits he mentions later in the video don't really apply to the 4D56/4M40 installations in Delicas. I.e. the EGR valve is not open at idle (low fuel and air already), and there is no throttle plate potentially causing pumping losses.
There are a few reasons you might want to remove the EGR valve... blowby oil going into the intake is the primary issue. This is more an issue of excessive blowby and not the EGR valve per-se.
An EGR valve that has failed/jammed in the open position (unlikely) will cause poor performance and much worse pollution. And a faulty EGR controller can also cause the valve to open when it shouldn't. But the most likely failure state is closed/inoperative (ECU failure/delete, bad vacuum lines/solenoids, etc); which is not uncommon and the same result as deleting it.
Another reason for the delete is because it provides convenient/easy locations for installing boost and EGT sensors.
There's a couple things about that video... firstly the two benefits he mentions later in the video don't really apply to the 4D56/4M40 installations in Delicas. I.e. the EGR valve is not open at idle (low fuel and air already), and there is no throttle plate potentially causing pumping losses.
There are a few reasons you might want to remove the EGR valve... blowby oil going into the intake is the primary issue. This is more an issue of excessive blowby and not the EGR valve per-se.
An EGR valve that has failed/jammed in the open position (unlikely) will cause poor performance and much worse pollution. And a faulty EGR controller can also cause the valve to open when it shouldn't. But the most likely failure state is closed/inoperative (ECU failure/delete, bad vacuum lines/solenoids, etc); which is not uncommon and the same result as deleting it.
Another reason for the delete is because it provides convenient/easy locations for installing boost and EGT sensors.