Have you ever checked your codes for you CE light?
I'm willing to bet you'll get a code for a stuck egr valve.
And I'm willing to bet that you have a pipe clogged with carbon from egr vapors. It's the hot inlet pipe to the intake manifold. Very common on these engines.
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I don't know about your state, but you couldn't pass a smog test with a tripped check engine light. It doesn't matter if the bulb has been taken out. The computer they use to test your car will pick it up.
2001 E430, Bourdeaux Red, Oyster interior.
1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".