'95 W124 OM606 - glow light comes on *after* starting

[tuxbeej]

Greetings, eh?

1995 E300D - glow plug light does not come on before starting, but it does light *after* starting.

Background:
Last week, I drove through a lot of mist when the car wasn't quite warmed up to 80C at 100 km/h. The car lost power and I was forced to slow down to 60 km/h, blowing white smoke. When we cleared the mist, the car got its power back and I resumed driving at 120 km/h.

A few days ago, we took the car out shopping. I didn't let it warm up at *all* and the car died three minutes from home. It refused to restart until 15-20 minutes of being parked, and even then once the engine "caught", I raised the RPMs to 1000 just to keep it from bogging down. I then slowly (paranoid, you see) brought it up to 3000 for 30 seconds, then up to 4000 at which point the car evened out. I dropped it to idle and it ran fine. Quite the smoke show too.

Last night, I drove it to Calgary **with no issue**. After three hours, I started it up again for the drive home and the glow light did not come on. I counted to ten, started the car, the engine ran fine, and the glow light came on.

I tried this again today and the car ran rough after starting, then evened out after a bit. Same thing with the glow light. It's 9C outside, BTW.

So... did I bugger up my preglow system? Do I have a bad glow plug now? What does it sound like to you?

(Also, I searched and read a couple of glow plug threads on here, but I may have missed the one with my answer. If you've got the link handy, please let me know and I'll go check it out. I *did* read one about a '79 240D already, which is where I got the "bad glow plug" idea.)

Thanks for your advice.

[compu_85]

You probably have a burnt out glow plug. The 1990+ cars are "smart" and can tell when a plug burns out.

-Jason

[tankowner]

Originally Posted by tuxbeej

Greetings, eh?

1995 E300D - glow plug light does not come on before starting, but it does light *after* starting.

Background:
Last week, I drove through a lot of mist when the car wasn't quite warmed up to 80C at 100 km/h. The car lost power and I was forced to slow down to 60 km/h, blowing white smoke. When we cleared the mist, the car got its power back and I resumed driving at 120 km/h.

A few days ago, we took the car out shopping. I didn't let it warm up at *all* and the car died three minutes from home. It refused to restart until 15-20 minutes of being parked, and even then once the engine "caught", I raised the RPMs to 1000 just to keep it from bogging down. I then slowly (paranoid, you see) brought it up to 3000 for 30 seconds, then up to 4000 at which point the car evened out. I dropped it to idle and it ran fine. Quite the smoke show too.

Last night, I drove it to Calgary **with no issue**. After three hours, I started it up again for the drive home and the glow light did not come on. I counted to ten, started the car, the engine ran fine, and the glow light came on.

I tried this again today and the car ran rough after starting, then evened out after a bit. Same thing with the glow light. It's 9C outside, BTW.

So... did I bugger up my preglow system? Do I have a bad glow plug now? What does it sound like to you?

(Also, I searched and read a couple of glow plug threads on here, but I may have missed the one with my answer. If you've got the link handy, please let me know and I'll go check it out. I *did* read one about a '79 240D already, which is where I got the "bad glow plug" idea.)

Thanks for your advice.

A couple things I would be checking here:

(1) As you suspect, check out your plugs. Do you know their history? Have they even been changed or are they original? If original then it is worth replacing them - change them all at the same time. You can find posts here on the job and also on using a bore reamer to get the gunk out.

(2) Changed your spin-on fuel filter lately?? If not, now is also the time.

(3) You might also take a look at your plastic fuel lines to see if there is any air in them. Use a light to shine through them as they have probably yellowed (browned?) pretty good over the years.

Good luck.

[Chris W.]

Glow plug light after starting indicates a problem with a glow plug, as mentioned. But even a problem with a glow plug only affects starting, and possibly running for a minute or two after initial start (the after glow period).

I am wondering about your "mist" episode. Glow plugs should have nothing to do with that behaviour. And smoking as well, again, should be unrelated to glow plugs. If your temp gauge is off the peg the car should run with no missing or funky losing power issues, or smoking for that matter.

When a glow plug failed on my car, the car would start, however one cylinder would not be firing, so it ran rough. Then as it ran for some seconds, the cylinder would start to fire, and you could hear and feel it doing so until it stopped nailing (from being cold and from having excess fuel from the misfiring) and settled down to running just fine, i.e. normal.

Loss of power is usually related to fuel filtration, if you have not changed filters this is a good start. If, after your car is good and warmed up, it will not wind to ~5000 rpm in first and second gear, that is a good indication that the main fuel filter needs to be changed.

I also had weird issues with stalling several minutes after starting just fine, solved by changing the lift pump.

If the car is rough running, plastic fuel lines are suspect, if they are dark brown and you can not tell from records when they were changed, it's a good idea to change.

Good luck and let us know how it goes.

Rgds,
Chris W.
'95 E300D, 323K miles, not klicks

[connerm]

In addition to everything already stated, I would bet money that your tank strainer is clogged with algae. The two most sigificant perforance enhancements I ever did to my 95 was to clean the tank strainer and replace the injectors. (I replaced them because I cannot find a source for Bosio nozzles)