ProV1

97 E420 119 engine, 105k miles

problems:
1. at idle or moving, there is a tapping/ticking noise that seems to be coming from the lower half of the engine (rod bearing?). happens at P, N or D. The tapping gets quicker when I shift to N/D than at P, and the frequency increases as I give more gas. What is the problem and how urgently should this be addressed?

2. Car has a rough idle (at D or P, but worse in D). At P rpm is a bit higher but at D when the rpm is at about 700, the rpm would drop to 400-500 and then the car would get it up to 700 again.. this happens every 15-20 seconds. Car doesn't die though. No engine malfunction codes.

fixnbenz

the ticking noise is probley the oiling tubes for the lifters they blow out the ends of the little plastic tubes and that lifter dosent pump up. now for the idle problem could be lots of things. but first i would try cleaning the throttle actuator. just remove the airmass and open the throttle with a screw driver and get some carb and choke cleaner and a small wire brush and clean off all the carbon. while your there check the breather hose to the valve cover and see if it is cracked.

ed austin

Replacing the tubes between the lifters sounds like what I need to do on a 2001 E320. Has anyone on here done it? Does anyone know of any DIY procedures on this job?

Thanks for any help.

lkchris

The M119 engine and your M112 V6 are different designs and yours doesn't suffer the same problem.

http://www.mercedesshop.com/Wikka/M119OilGuides