EGR Removal

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EGR Removal

Post by zealost »

No, this isn't the usual question, about ' how can i remove it'. I'm only asking... WHY remove it? .. and someone told me that it only heats up the [exhaust] or something .. meaning, bad. I'm actually clueless, so i thought i'd throw the question.
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Re: EGR Removal

Post by andyofcolumbusmerkur »

It puts a little bit of exhaust (with little to no oxygen left) into the combustion chamber which gives you slightly better fuel mileage. It is like the engine is slightly smaller displacement. Most cars got fixed for free at the dealer (search emissions recall modification) and now the egr supposedly never activates at all or it is very rare. So I didn't feel bad not even running a vacuum line to it. I just loop a small piece of vac line between ports on the vacuum tree so I don't have a huge leak.
If it was easy everybody would do it.
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Re: EGR Removal

Post by Ed Lijewski »

Exhaust gas is a slightly lower temperature than combustion temperature so adding it to the intake, when needed (per the ECU), lowers the production of Nitous Oxide (NO2) at the tailpipe. NO2 is an undesirable exhaust emission with respect to human respiration.

The EGR is activated only under certain engine load conditions. Keeping it installed and working detracts little from enjoying an XR's performance at various throttle positions.
Screenshot_20220510-213115_Chrome.jpg (319.17 KiB) Viewed 821 times

Link is to excellent description of the EGR by Larry Carley who writes on all aspects of internal combustion engines: ... ulation%20(EGR,that%20contribute%20to%20air%20pollution.

Last edited by Ed Lijewski on Tue May 10, 2022 9:37 pm, edited 2 times in total.
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Re: EGR Removal

Post by my8950 »

EGR is the exhaust, already burnt air mass in the cylinder.
Since it is already burnt, the oxygen content is much less than fresh air.
By mixing this in the cylinder, you're putting inert gas back in, less oxygen, less NOx.
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