Have reviewed applicable threads, but can't find anything quite like my problem. Would appreciate help.

Live in northern Virginia ... getting cool, now. On key-on, glow plug lamp illuminates, then goes out ... seems like a normal start (I replaced plugs a couple of years ago). About as smoky as it has always been. Glow plug lamp goes out.

After about 10 seconds the glow plug lamp re-illuminates and stays on for almost exactly 60 seconds ... very consistent - not engine speed or outside air temperate related. If I turn engine off (whether I pull key to restart or now), the restart sequence is abnormal in that glow plug lamp never illuminates at all.

If car sits for a few hours, the cold start sequence described above occurs, again.

Remainder of operation is normal ... glow plug lamp DOES NOT illuminate while normally driving ... i.e. no intermittent operation, just during post start sequence.

What say the assembled?

Thanks!

__________________
George Stephenson
1991 350 SDL (200K and she ain't bent, yet)
former 2002 E320 4Matic Wagon - good car
former 1985 300 CD - great car
former 1981 300 TD - good car
former 1972 280 SEL - not so good car
a couple of those diesel Rabbits ...40-45 mpg

I cannot comment on the specific nature of the 350, however, every time that light has done things that are not expected on mine, one or more than one of the glow plugs are not working properly.

I believe that the first thing you need to do is to check each glow plug with a sensitive ohmmeter and verify that the readings are below 1 ohm on all of them. If you find any that are above 1 ohm, or open, change them.

If this fails to resolve the problem, then the relay might be the culprit.

One or more bad glow plugs. Change them ALL, they are the same age, with bosch or Beru.

__________________
N. Hodges
1994 S350
1987 300 SDL (for sale)

nhodges,

Thanks ... I replaced all about 2 years ago with Bosch ... sounds like I should test them all .... not so common for one to go out this quickly?

Can I test without removing them? Other contributors of answers to my thread indicate should do this ...

Thanks, again, to everyone!

__________________
George Stephenson
1991 350 SDL (200K and she ain't bent, yet)
former 2002 E320 4Matic Wagon - good car
former 1985 300 CD - great car
former 1981 300 TD - good car
former 1972 280 SEL - not so good car
a couple of those diesel Rabbits ...40-45 mpg

stephenson,

Do a search on "resistance" or "GP resisitance" or "glow plug resistance" and you should find the precedure to check the resistance of the GP.

If you don't find anything, tell me in another reply and I will "splain".

BTW, which model and year MB are you asking about? Always clearly specify model and year with your question.

P E H

PEH,

Sorry ... title of thread had model, but not year ... 1991.

Will do search ... thanks.

__________________
George Stephenson
1991 350 SDL (200K and she ain't bent, yet)
former 2002 E320 4Matic Wagon - good car
former 1985 300 CD - great car
former 1981 300 TD - good car
former 1972 280 SEL - not so good car
a couple of those diesel Rabbits ...40-45 mpg

Lots of folk have the time and patience to test them all. Do so if you desire. It is a PItA for me, so I just replace them and do something else with my time.
The first check I would make is to see that the glowplug wires are not grounded to anything.

__________________
N. Hodges
1994 S350
1987 300 SDL (for sale)