For the past couple weeks I have had a P0300 (Multiple Cylinder Misfire) Check Engine error code. I have reset it and after a couple days it seems to come back on. I took the vehicle to the dealer to get an oil change done last week and it has not come on since.

Couple questions/comments:

Is this something major that I should get checked out?

I have not noticed a decrease in power from the vehicle when this error is triggered.

Could this be related to ULSD?

I have not driven the car much since the switchover but recently I have been driving the car fairly frequently and I have filled up maybe 10 times since ULSD came out.

I am hoping its not something major but if it is I would like to know so I do not cause further damage to the vehicle. After the oil change the light has not come on for the past week or so....Thanks

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2005 SL65
1999 E300
1995 E300
1994 SL320
1988 560SL
1987 300TD
1982 300D
1955 300SL

I doubt it is related to the fuel since practically everyone here is using the same ULSD fuel and nobody else has had this issue come up. Are you waiting for the glow plug light to go out each time you start the car when it is cold? If so I would think it is possible you have a weak or blown GP that is causing a misfire. Does it start smoothly from cold or does it shutter and shake for a few seconds?

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Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz

it starts on the first crank, with some very mild shaking, there is a slight stutter between 800-1000 rpm. I always wait for the glowplug light to go out before starting.

There have been times maybe 30-40k miles ago where the glow plug light stayed light, but went away. I haven't changed the glow plugs, since I have had the car 5 years and 60k miles. (Car has 86k miles)

Car drives smoothly, and acceleration is very brisk..I am hoping I do not have any bent rods.

If this was some sort of a major problem would I notice a decrease in power etc?

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2005 SL65
1999 E300
1995 E300
1994 SL320
1988 560SL
1987 300TD
1982 300D
1955 300SL

This engine is not famous or known for bending rods. That was the 3.5 liter in the "S" Class models from 1990 to 1994. The 1999 E300D TurboDiesel you have is likely having a problem with glow plugs, especially if you had an indication from the glow plug light and have not done anything to address it.

Jim

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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)