Diesel Glow plugs
 

Can anyone help please......... I maintain my own vehicles and have done since I was 17, 35 years ago. I have a problem with my 220 CDI Estate, on cold start the glow plug lamp lights, the engine starts and runs fine, but a few seconds later the lamp comes on again for perhaps 10 seconds. I havent owned the car long and it has only just started doing it. The weather has turned cold 5 to -2 degrees. Is this normal or does this indicate the glow plugs need changing. The car is nearly 4 years old and covered 55000 miles.

Thanks in anticipation. Delboy

Take an ohm meter to the plugs. Good ones will measure about 0.6 ohms cold. Lots of info on this in the archives.

Len

I'm not familiar with the newer models but it sounds to me that if it starts fine with no missing that the plugs might be ok. Maybe the relay is messed up, sending another light signal when it shouldn't? Hopefully someone with more experience on that model can help.

Pull the glow plugs and hook them up accross a battery (hold them with pliers). If they do not glow bright fairly quickly then replace them.

Yes they do wear out.

Check out how to test glow plugs on this pictorial

http://dieselgiant.com/mercedesdieselloopglowplugrepair.htm

the only symptom
 

is the lamp comes on a bit after it is started? starts and runs fine even in very cold weather? seems like no problem to me if that is true.

also year of vehicle will help.

tom w

Thanks for all the replies and response, tom the year is 2002. I will pull em and test on ohm meter.

Keep us updated on what it is.

You don't need to pull the glow plugs to test them with an ohm meter. Just unplug the connector and test them at the terminal.

Len

The is absolutely correct!