It seems my glow plugs are not working at all. The car begins the starting ritual normally, the glow plug indicator light lights up, then goes out, I turn the key to the start position, the engine cranks, it fires, and runs making loud and unusual for this Diesel engine, clanking noises. The glow plug light comes back on, and the dashboard message center lights up in big ugly letters saying to check the engine electronics. Anybody got a clue if this means the relay is gone, or if I need to check the plug resistance and find a bad plug? Jim

__________________
Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)

The GPs are not in series but in parallel and it is unlikely that if they were working prior to this that more than one went out at one time. I would start with the relay and see if there is voltage going to the GPs when the glow cycle is initiated. I doubt it is the plugs but you can easily check them for resistance right at the connector for the relay.

__________________
Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz

I pulled the connection on the driver's side inner fender for the glow plugs, and tested the power to that point (a-ok, about 11.8 Volts) and then did a continuity check to each plug from the female receptacle. The receptacle has six connections arranged like the six spots on dice. 5 were between 1.1 and 0.9 Ohms. One was infinite. Is there a key so I can decode which one is the bad one? By "key" I mean, is there a means to identify which socket on the female receptacle is which glow plug. This used to be marked right on the plug/receptacle on older cars, but I could not see anything like that. Thanks, Jim

__________________
Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)

If you are lucky you can pull the connectors off the GPs you can reach without removing the intake manifold and check for continuity to each of them. If it is one you can get out without pulling the IM you will save an hour or so of your time and the cost of the gasket. If you do have to pull the IM I would recommend just replacing all 6 as preventative maintenance though so you don't have to pull it again when the next one goes. I also recommend using the MB OEM GPs rather than aftermarket. They are pricey but I have heard of some aftermarket ones burning out very quickly and if you have to pull the IM again you will lose all the savings in lost time.

I also recommend you apply a good quality conductive anti-seize compound to the threads of the new GPs. There is one which is copper based and costly but I have heard it is the best to use and is what I used when I changed mine. Mine were original from 1998 from what I could tell from the service history and came out without a problem after 115K miles but some have not been as lucky.

__________________
Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz

The glow plugs don't have to be your problem.. could be the mass air flow sensor (MAF) or a number of things. Is the "check engine" light on? If so, have it scanned.

If you've got one plug reading infinite, then you've got a bad plug. The plugs are numbered on one of the pieces of the glow plug relay. You have to look very closely and you have to have good eyes, but the numbers are there. I think the odd numbers are on top and the evens on the bottom.

Also do a search on this forum. There are excellent posts about doing this job. No matter how careful you are, I thibnk there is a chance that you might break off a glow plug. Bad design that we've got to live with. I broke one off and had to drill it out when I did it. I also used antisieze and will again, but I'm not convinced that will make it any easier the next time. I think the glow plug welds itself near the tip via the carbon and I just don't the antisieze will prevent that, but it won't hurt anything, that's for sure.

Len

Well, it looks like it is a glow plug the way I see it, and I will find out which one in the morning, then order the necessary gaskets and so on, so I can do the deed next weekend. I will plan on trying to remove the gunk from inside the intake manifold - anyone recommend a solvent or other means? If the bad one comes out ok, I will probably remove the whole lot and change them, depending on how much of a pia the intake manifold removal turns out to be.

Wish me luck, Jim

__________________
Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)

I tried a couple of things and ended up using POR15 Marine Clean. It did a fantastic job, quick and easy. Made it sqeeky clean.

Manifold removal is very easy after you've done it a few times. There is one very good post about it. See Finally - Step By Step Glowplug Change - '98-'99 E300!

Len

That was a great post. I recall reading it earlier and was not looking forward to finding it next weekend. Thanks for the information, and I will be studying the posts you guys have made over the next week or so. I am considering running the machine good and hot - like up a steep hill in low gear and WOT for a while, to try to burn and blow out any big carbon deposits to try to make the glow plug sticking mechanism less likely to bite me. Jim

__________________
Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)

After 65K on the clock, my problem was that the threads locked together. None of the other stuff had much carbon in them. I coated the body with anti-sieze with only the tip uncoated. Also I plan to take them out every year just to be safe. There is a gasket betweent the manifold and the intercooler. Change it too.

__________________
01 Ford Excursion Powerstroke
99 E300 Turbodiesel
91 Vette with 383 motor
05 Polaris Sportsman 800 EFI
06 Polaris Sportsman 500 EFI
03 SeaDoo GTX SC Red
03 SeaDoo GTX SC Yellow
04 Tailgator 21 ft Toy Hauler
11 Harley Davidson 883 SuperLow

Well, the job is underway and I have a question and an observation to share. I am replacing the plugs and have two new part numbers. One ends in 2101 and the other ends in 2001. The 2101 plugs seem to Beru and the 2001 plugs seem to be Bosch. I am only replacing the 2 that seem bad, which would be number 2 and number 6, based on what I have read about this issue and the potential for disaster. I got #2 and #6 out without any real problem, no thanks to the German genius who made getting a standard wrench on them unnecessarily challenging, except I noted the number 6 plug was only hand tight. I thought I broke it off without trying for a second. Number 2 came out and was clean all the way to the tip. Number 6 was covered in what looked like wet black crap, but turned out to be baked on hard, shiny black crap.

Once you get the hang of getting the manifold off it is not that much of a barrier for the next time. I will leave the plugs that are ok in there and live to regret this decision when the next plug fails in the winter and I have to lay on my back in the snow to get that Allen head bolt off the connection to the intercooler.

I am beginning the cleaning of the manifold. Anyone want photos of anything in particular, speak up. Jim

__________________
Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)

Once I got into cleaning the manifold I got pretty frustrated. The EGR valve assemble is connected to the intake manifold using a four bolt flange and metallic gasket. Mine was leaking and had spewed a large black oil streak on the underside of the manifold. So, I took the fasteners between the EGR valve and the manifold off and found the gasket had been folded over at one corner so for a quadrant there was no gasket, and that part of the gasket was on the inside, blocking the air passage. I repaired the gasket as well as I could and will be stuck reusing it.

What cleans that goop out of the intake manifold? I have tried everything you guys have listed but Diesel. The stuff gets soft and sticky but does not dissolve. Looks like I will be going out to get a gallon of Diesel and maybe some more Gunk carburetor cleaner or other automotive solvent. Jim

__________________
Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)

I sent it to a machine shop to hot tank the thing. They would remove the EGR first. That I cleaned with carb cleaner. If I were you, I would remove the other 4 GPs and reinstall them with anti-sieze just so they won't stick on you next time.

__________________
01 Ford Excursion Powerstroke
99 E300 Turbodiesel
91 Vette with 383 motor
05 Polaris Sportsman 800 EFI
06 Polaris Sportsman 500 EFI
03 SeaDoo GTX SC Red
03 SeaDoo GTX SC Yellow
04 Tailgator 21 ft Toy Hauler
11 Harley Davidson 883 SuperLow

I tell ya - that POR15 Marine Clean was fantastic at removing that black gunk from the manifold - fast too.

I agree with Aklim about the other four plugs. I'd at least try to loosen them. If they unscrew reasonably easily, change them. If any seem to be really stuck, maybe let that one go. If I had to do mine over again, I would have left my #2 in place and stopped trying 1 nm before it broke.

Len

if i did all that you can be sure i would not scrimp. i would change them all! bosch.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.