Have 96 Diesel 300 Mercedes with 136000 miles. Had problems with Glow plug 30000 miles ago and resolved problem. Now yesterday check engine came on while driving then a few seconds later glow plug came on for about 20 seconds then vanished. Today when starting everything appeared normal when starting but check engine light stayed on but glow plug light did not stay on which I thought was good. Going to have car computer analyzed for code to see problem. Recently 2000 mile ago I had new K-40 relay installed which resolved problem with stalling and starting. Just hope this is not a more serious problem. Any thoughts and Happy Labor Day

Did it get analyzed Yet?

You could use a Volt/Ohm/Multimeter check Glow Plugs by way of the Diesel Giant Glow Plug repair Pictorial (this is not a recommend to buy parts there) just to gather more information.

If your Glow Plug Relay has a Strip Fuse check that for Cracks or loose Screws that hold it down.

When the Glow Plugs are changed Reaming the out the Glow Plug Holes with a Glow Plug Reamer or finding an alternative method to clean out the Carbon the adds to the life of the Glow Plugs.

Use only Bosch or Beru Glow Plugs.

__________________
84 300D, 82 Volvo 244Gl Diesel

I have to wait till Tuesday morning to have the code read. I was hoping that the check engine light would turn off but no such luck. Am still hoping that it is not a costly repair. Probably should never have stopped the additive that I was using to clean the carbon from the valves etc. This is bad timing since I was going to let someone use the car because I am going out of state for a few months. I would hate to have the car break down completely while I was gone and cause personal anguish for the family member using it.

Any thoughts on glow plug light sometimes coming on during pre-start but now not coming on till after started then it turns off. I realize that light is supposed to come on before starting and just hope that this not causing more problems. Any thoughts.

When the glow light lingers after start on a 210, one (or more) glow plugs are bad. Easy way to confirm if you have an ohmeter. Remove the six-pin connector on the driver's fenderwall, measure resistance from each contact to ground. Good glow plugs will read 1-2 ohms, bad ones will read open circuit. Each of the contacts on the connector are numbered to tell you which glow plug, but you need bionic vision to see them. Report back when you find the bad GP and get the proper removal procedure.

__________________
Mark in MA
05 MB E320CDI 402k Granite Grey Metallic
05 MB E320CDI 267k Black
05 MB E320CDI 232k White
05 MB E320CDI 209k Tectite Grey
99 Dodge 2500 Cummins 5sp 148k
62 Jeep CJ-6 120k