So It is really cold outside, about -10 degrees, and my 1985 300td wont start. the coolant lines are warm so I know my block heater is working. It seems like something is wrong with my ignition. Some times the glow plug light will come on and sometimes it wont. I checked the plugs with a multimeter and they are all good. There is a lot of play in the ignition when I turn the key. When the car was running I would have to turn the key very slightly to the left to get the blower motor for the heater to work. I could hear the relays click when I tured the key to the left. Today there were even times where the key would not turn in the ignition.

Has anyone had this problem before?
If so I could really use some help.

State, exactly, how you performed this test.

I set the multimeter to 1000 ohms I touched the ground to the block and the positive to the tip of each glow plug. Three of the plugs registered 0 and were actually burned out, so I replaced them. The back two plugs registered about a 7.

Test is invalid.

You need a meter that can read below 10 ohms. Set the meter to 10 ohms and repeat the test.

Each glow plug should read about 1 ohm.........up to 1.5 ohms is acceptable. Anything over 1.5 ohms needs to be replaced. Anything open needs to be replaced.

With three bad plugs, the odds of the remaining two being excellent are nil.

You need "excellent" in the cold.

Because my valve seals leak a little,I've found that changing glowplugs before winter fun.No worries.
To crippled to do valve seals.

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1999 w140, quit voting to old, and to old to fight, a god damned veteran

If you can't ohm the glow plugs like the other members suggested,
remove the glow plugs and test them using a jumper cables with direct 12 VDC,
ground to the glow plug body and positive to the tip where the wire screws in,
look for a red amber tip, keep fingers off hot plugs.
The ignition tumbler being loose, it's time for replacement do not delay,
or you will have a heck of time replacing it if the key doesn't turn.

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1986 190D 5 cyl. 5 speed manual White (215K),
1983 300SD Silver blue (103K)

Here is the Diesel Giant Site with the pictorial how to do the Glow Plug check.
http://www.dieselgiant.com/glowplugrepair.htm
I think on my Multi Meter the Lowest setting is 200 ohms.


For your lock/ignition problems
Ignition Cylinder Tumbler replacement; mixed diesel/gas


I do not know if WD40 can freeze up at -10; the alternative is powerded Graphite that comes in a little squeeze tube;but if you squirts some in the Key Hole and it becomes easier to use it could mean your Ignition Key Tumbler is on the way out.

If it turns out the Ignition Switch itself is bad. I can access mine after the Kick panel is removed looking up from below. 2 screws hold it in place.

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84 300D, 82 Volvo 244Gl Diesel