A bypassed EGR will not hurt the car. In fact it should help keep your intake manifold clean on the inside. You should also get slightly more power and slightly better mileage. EGR is used to control NOx emissions. It does so by slowing the rate at which your fuel burns allowing a more even distribution of heat in the prechamber.

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green 85 300SD 200K miles "Das Schlepper Frog" With a OM603 TBO360 turbo ( To be intercooled someday )( Kalifornistani emissons )
white 79 300SD 200K'ish miles "Farfegnugen" (RIP - cracked crank)
desert storm primer 63 T-bird "The Undead" (long term hibernation)

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