It seems that when my 95 E420 sits in the garage for 2-3 days it shakes and hesitates at idle when I first start it then goes back to normal after I drive it for few minutes… any ideas on which direction to start tracking the problem down. No faults are reported by the system. What shall I be looking fore?

Few weeks ago same happened and took it in and the service tech couldn’t duplicate the hesitation. Would this be related to Spark plugs and/or EGR valve and/or… what order shall I start with? Car has only 41,500 miles and up to date with maintenance (new plugs, fuel filter, air filter etc all done last year)

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Joe95E420

Cold start valve? AKA, fuel enrichment valve.

inspector1,
Any ideas on where do i find this valve on my M119 engine?

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Joe95E420

I had a similar problem a few years back and the problem was a bad spark plug connector to the spark plug itself. The dealer diagnosed it when they put it on the scope and they only charged me ~100 to diagnose and fix. The car 92 400E.

Does anyone know how to test for spark plug connectors? any tricks? Can i test with an ohmmeter? what shall i be looking for? thanks.

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Joe95E420

I am told there is no Cold Start Valve on this car... any ideas?

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Joe95E420