Hi all,

'85 300sd 150kmi. I cruised about 300mi on the freeway yesterday @75mph. The car ran fine as usual, no problems accelerating or cruising. When I got off the freeway, the car would seem to 'miss' at idle, like it wanted to die. It never died, but would intermittantly miss, like one or more cylinder wouldn't fire. It never dropped below 500rpm, but the miss is disconcerting. This has happened twice before, but not as severe as yesterday.

Is this an injector, timing chain, or valve issue?

Thanks in advance the the advice.

Was the car a "city car" before this long trip? If so, all of that driving at 75 mph probably got to some of the carbon in the engine and "rearranged" it., making it run rough now. I'd try some more highway driving and see if that helps clear the rest of the carbon out.

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'81 MB 300SD, '82 MB 300D Turbo (sold/RIP), '04 Lincoln Town Car Ultimate

Sooner or later every car falls apart, ours does it later!
-German Narrator in a MB Promotion Film about the then brand new W123.

yep just do another "italian tune up"

The rack damper bolt needs to be checked to be sure it is not the weak spring one.

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1981 300D 147k
1998 VW Jetta Tdi 320k
2001 Dodge Ram 2500 141k
1979 300D 234k (sold)
1984 300D "Astor" 262k(sold)
Mercedes How-To and Repair Pictorials
I love the smell of diesel smoke in my hair

Hi,
sounds to me more like a clocked fuel filter

they will leak the most after getting good and hot if they are tight or burned. the heat expands them.

tom w

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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.

Classic rack dampner issue. Adjust or replace, neither is hard. Try a search.

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1984 300Sd 210k

Former cars:
1984 300D 445k (!!) (Strider) Original (and not rebuilt) engine and transmission. Currently running on V80 ( 80% vegetable oil, 20% petroleum products). Actually not, taking a WVO break.
1993 300d 2.5 275k. Current 120/day commuter
1981 300SD 188k (Hans) Killed by a deer