Ther corelation between the light on the dash and glow plugs may not be there. You have to monitor from one of the glow plugs to ground with a meter or test light with someone telling you from inside the car what the dash indicator is doing. A meter should indicate about 11 volts or close. If that voltage is not there at all then you check the strap 80AMP fuse strip out.. It is a strap fuse that can corrode or otherwise go bad at any time so check it out first if voltage is missing on glow plugs. If the plugs are not staying on as long as the dash lite then may be a relay problem. On bosh equipment the presence of the dash indication of cycle does not absolutly mean the plugs are powered up. Or on as long either but that is more unusual. A little while back I think you were describing about I ohm per plug from the harness all about equal and that sounds about right. On the fuel issue I did forget the algea issue as a possibility but first establish that glow plugs are really coresponding to dash indicator as well as following someones given good suggestion to make sure you are getting fuel by loosening injector lines to verify output or not. Diesels tend to confuse but generally if heat, fuel and air are provided in proper sequence with reasonable compression they run. Sad they cannot be a little quiet about it but on the otherhand if it starts you will not miss the event. Car sitting awhile plus overfuelling may release a few particals of smoke initially. Thats why mercedes made their diesels smoke so bad after sitting for awhile. Even totally deaf people cannot miss the startup.