I know i asked this once before, but i have some new information that someone may be able to recognize as a symptom of.......
The glowplug light will not come on when the temp drops below 65 or so. Period. Once the engine is up to normal operating temp and you start it up right away(running into convienence mart etc..), the glowplug light works fine(big help then!) I can still start the car, but when it is cold i MUST pump the accelerator, and then it fires, however missing badly, the misses clear up in about 2-3 seconds. When i start it this way i also notice an absurd amount of smoke coming out the exhaust and it's really quite embarrassing(especially in front of two fine girls who just complemented you on your mercedes!!!) When the plug light did work most the time(about a week ago) the car fired right up no problems at all, and smoked VERY little. It seems to me that if it were a glowplug itself that the light would be out all the time, and not work when the car is warmed up or it is warm out. Sometimes the light doesn't even come on when it is warm out, but it isn't a problem then, and that only happens about 1 out of 20 starts(when it's above 70 or so). ANy thoughts on this? could a bad plug really cause this even though it's intermitent?? One more question, the car is a 83 300SD, i was wondering how long it should take the car to get to normal operating temp when it's 60 degrees outside, it takes it about 10 minutes right now. Thanks
R

I would check all of the wires and connectors for your glow plugs...

The reason your car smokes is because as you said, you pumped the accelerator several times and got excess fuel, and that fuel needs to be burned off hence the smoke..

Find and check the temperature sensor for the glow plugs -- sounds as though it is not working correctly. The wire could be loose, too. And you may have a defective relay or bad or corroded fuse. Most likely the temp sensor, since the glowplugs work warm.

You probably have a bad thermostat that opens early or doesn't close completely. It can take a few minutes for the diesel to warm up, but mine (at 32F) only takes 2 miles to get to operating temp.

Check your coolant, too, it may be low!

Peter

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1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

alright thanks, i've already got the new thermostat, however the top bolt out of the three is extremely stripped. The person who had the car must have used an impact wrench on that thing!, i've tried everything to get that bolt out, i even hammered on the wrong sized wrench, tried vice-grips, and of course i tried to use the regular right sized wrench before i did all that. I'll take it up to my local mechanic and have the thermostat replaced i guess. Where is this temperature sensor? is it expensive or can it most likely be repaired?
thanks
R

Hey kiddo:

Very good example of why I tend to use anti-seize on steel bolts into aluminum, specially where coolant can get on it. The bolt is well and truely seized. Very new, sharp vice grips might help -- the jaws get rounded off pretty fast. Probably need to let someone else get it out.

The thermistor is in the glow plug relay, alas. There are some threads on how to test it, I think, do a search. All but the two newest of ours have external temp sensors, and I've not yet had to fix one of the new ones. You will have to replace the relay if it is shot.

Nitpicky crap like this is why people sell the older benzes so cheap -- imagine paying someone $100/hr to fix this stuff!

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

no kidding about the 100$ an hour to fix this little stuff. When i bought the car it was full of 500 dollar estimates to fix that this and the other thing. The most memorable was when i looked at an estimate to fix the rear window regulator to the tune of 362$ I fixed it for 12 bucks I was also told that my blowby would require a top-end rebuild that was very pricey(in the 1000's) that i have managed to fix by driving it harder then it had been in the past. Thanks for the tip on the temp sensor, i'll do a search and let you know what i come up with. If it is the relay is there anyway to jump it temporarily, i don't have the spare cash for a relay at the moment but it is getting pretty cool out there, thanks
R

Have you pulled the top off the glowplug relay box and removed and inspected or replaced the 80A fuse. I have seen them with fine cracks that are not detectable while in place. The relay is forward on the drivers side fender. The fuse is a strip of metal held in place by two screws. There is a removeable cover on top of the relay.

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Bob D.
Parrish, FL
1 SDL, 1 D, 1 TD, 1 Mog

You can pump the accelerator all day on a Diesel and you won't flood it. There is no throttle pump in a Diesel like in a carburator. All pumping the throttle does is move the rack in the injection pump (IP) which changes the amount of fuel the IP will deliver but no fuel will be delivered until the plungers are moved by the cam in the IP. Its like pumping the accelerator on an electronic fuel injected Gas engine, nothing happens. ~~~~~~~PEH~~~~~~~~