Plug the 2 plastic vacuum lines that lead up to the valve cover switch. Plug them independently, i.e., don't plug one into the other, just block them both. The transmission will behave as if there are no leaks in the EGR system affecting the shifting (because they're not connected)

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'82 300SD - 361K mi - "Blue"

"Good judgement comes from experience. Experience comes from bad judgement."

listen, look, .........and duck.