1994 Mercedes Benz E420 Idling problem in Drive

1994 MERCEDES BENZ E420
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SUNDERDUE
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  • 1 POST
Engine Performance problem
1994 Mercedes Benz E420 V8 Two Wheel Drive Automatic

This car idles ok (rpm is 700) when it's in park or netural but, when the car in drive the Tac goes from 500rpm to 750rpm at one sec intervals. The car has 161000 mi and is in good condition otherwise. The vin is as follows:

WDBEA34E8RC078952
Mar 20, 2009 at 9:32 AM
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KHLOW2008
  • ASE Certified Mechanic
  • 41,814 POSTS
  • ASE Certified Mechanic
Hi sunderdue, Thank you for the donation. The symptoms described indicates a vacumn leakage causing the engine to hunt.


https://images.2carpros.com/forum/automotive_pictures/192750_VacumnControl94MercE42003_1.jpg


https://images.2carpros.com/forum/automotive_pictures/192750_VacumnControl94MercE42001_1.jpg


https://images.2carpros.com/forum/automotive_pictures/192750_VacumnControl94MercE42002_1.jpg

Mar 20, 2009 at 10:50 AM
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