Michael:

The heater is above and behind the IP -- fuel from the lift pump it circulated through it when the temp is low. Can cause hard start problems if the o-rings go bad and let the fuel leak back into the tank.......

Of course, it won't help if the fuel in the filter is solid, though!

ezrider:

Intermittant rough idle on a 603 can be dirty injectors or bad engine mounts. If you cannot see the tapered portion of the mounts on the bottom, or if there is obviously oil leaking out, you need new ones. Very easy to replace if you have jack stands and a floor jack, or an engine hoist to lift the engine. One bolt top and bottom.

The notorious bent rod problem is evidenced by horrible engine clank (not injector noise) and excessive oil consumption, often occuring suddenly. Injector knock isn't a cause for alarm.

You may also have defective tappets, or bad o-rings on the center "bolt" on the oil filter housing cap -- if they are rock hard and leaking, the oil will leak down out of the tappet gallery and cause loud tapping noise and rough idle until the tappets re-fill. The o-rings are not in the oil filter package, you must get them separately.

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!