Benz Forum banner

1 - 6 of 6 Posts

·
Registered
Joined
·
4 Posts
Discussion Starter #1
Can anyone give me advice on heater plugs on my e300 td.
I have had to have them replaced quite often lately. My garage tell me it's too expensive to change the whole lot, so I just change the particular one when it goes,which costs about £80.
Regards.
 

·
Registered
Joined
·
78 Posts
I would probably change out all of the glow plugs at the same time. If one of the glow plugs is curently bad, it probably won't be long until another one is bad also. On this engine, I'm not sure how much has to be removed just to get to the glow plugs, but, on some engines this could this could be labor intensive to only change one plug at a time.

Ken
 

·
Registered
Joined
·
44 Posts
We had one plug go bad under warranty. It was replaced and within a fortnight (added that since your're a brit :wink:) another failed. The dealer changed all 5 remaining at that service. No problems since and that was bout 4 years ago. Except for the warning light being a PITA I think you could get by with 2 or 3 bad glow plugs. You would run rough for only a few minutes until the cylinders got hot. I guess my suggestion if you like the car and plan on keeping it is to replace all the remaining plugs.

Bob Skillman Ellicott City MD 98 E300TD
 

·
Registered
Joined
·
3 Posts
Testing your Glow plugs

To test your glow plugs is simple. This needs to be done when the engine is dead cold. Each glow plug has an individual lead wire to it, all color coded. These 6 wires go to a relay on the front left fender (driver side USA, passenger side UK). Pull the single plug-in off of the relay exposing the 6 leads on the wire loom. Using a mulimeter on the OHM setting, test each glow plug lead (multimeter wires: one to the glow plug lead the other to a good ground). The good range of the glow plug should read 0.5 to 0.8 OHM's. Bad plugs should be replaced. Here in the USA the Bosch plugs cost about $23 each. Replcing them is not hard, you just need some time to remove the bolts fastening the intake manifold to the head and there's one bolt to remove from the BOTTOM of a bracket holding the manifold to the intake pipe that goes to the intercooler (which is located below the radiator). I also beleive if a glow plug is bad the glow light will stay on all the time. Did youu also know that even though the glow plug lamp goes out (indicating to start) that they actually continue to "burn" for up to 2 minutes AFTER the car is running? This extra glow burn provides extra heat to diminish the exhaust smoke on warm-up.
 
1 - 6 of 6 Posts
Top