The vacuum line is likely the reason for the SES light, and hopefully the reason for the bogging. The threaded hole would be for a bracket to hold something, like the metal cross pipe between heads for the secondary air system. If there is nothing there, no big deal... likely not used.

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"When you do things right, people won't be sure you've done anything at all" (Bender, futurama)

You make something idiotproof, they'll make a better idiot

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X5 pics

RIP 4.6is.....

2003 4.6is