1997 e300 NON turbo with 131k miles. 3 week old issue. checked all vacuum tubes,connections - ok, cleaned the cross over tubing, flaps cleaned- the list goes on.It used to light up on idle - now it's only lighting up when I accelerate and push the accelerator almost past half way point. Car runs perfect otherwise

There are only 2 things I'm debating to replace, either the vacuum transducer attached to the air filter box that feeds vacuum to the EGR, or the EGR itself.

QUESTION: How do I check these components on the bench to make sure that it is bad?

Thanks for the help

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a2


1978 280 CE silver
1986 560 SL black
1987 300 SDL cream
1994 SL 500 brilliant green
1997 E 300d dessert silver
2005 FORD F250 Superduty Crew cab 4x4

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