Sorry, I'm sure this has been covered but I haven't had much luck finding info by searching. My 82 300SD has just started to not shut off when I turn off the key and remove it. It does it every time now. The last time it did shut off after about 30 seconds but it usually just keeps going. usually I have to lift the hood and use the "stop" lever.

what is the most likely cause?

You have a vac leak, and as luck would have it, it could have the most info of any other topic if you search.
It would be hard not to find info on this......

:EDIT:
Search: Key Word(s): shutoff, valve ; Forum: Diesel Discussion

Search: Key Word(s): runaway, diesel ; Forum: Diesel Discussion

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Jimmy L.
'05 Acura TL 6MT
2001 ML430 My Spare

Gone:
'95 E300 188K "Batmobile" Texas Unfriendly Black
'85 300TD 235K "The Wagon" Texas Friendly White
'80 240D 154K "China" Scar engine installed
'81 300TD 240K "Smash"
'80 240D 230K "The Squash"
'81 240D 293K"Scar" Rear ended harder than Elton John

Apparently not:

Sorry - no matches. Please try some different terms.

I'm new to diesel's so I had no clue as to what may cause it. Now that I know its a vacuum leak, it narrows it down a lot. Doing searches on "continues to run" or "won't shut off" leads to 20 pages of results.

Thanks for the reply.

Try searching "runaway deisel"

Get a miti vac and test the vacuum.

The shutoff is usually a brown hardline. Running backwards, the vac line to the fuel shut off is on the IP. It runs to your ignition switch, from the switch is connects to a 3 or 4 way connector, which is the connected to your vacuum source.

A miti vac will hel you find what is leaking. A vacuum leak in another device can cause the car to not shut off.

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RRGrassi


70's Southern Pacific #5608 Fairmont A-4 MOW car

13 VW JSW 2.0 TDI 193K, Tuned with DPF and EGR Delete.

91 W124 300D Turbo replaced, Pressure W/G actuator installed. 210K

90 Dodge D250 5.9 Cummins/5 speed. 400K

Amazing, the OP is correct. it is VERY hard to search for solutions to this.
I know exactly what causes it, and I have tried several searches and cannot find any pages that help with it.
John
oh, check the vacume lines connected to your key switch, the ends tend to deteriorate. also pull the brown line from the modulator looking thing on the IP and see if it has oil in it.
John

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My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
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1987 300TD
1987 300TD
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If it just started, rather than go through a lot of detail searching, it would be easier to just look under the hood and see what came loose after working on it last. Even with an oil change, it is very easy to accidently dislodge a vacuum line and cause this.

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Sam

84 300SD 350K+ miles ( Blue Belle )

My brown line that goes to the ignition just snapped in half while I was removing the GP relay cover. 20 year old plastic is brittle.

Don't know how it connects on the W123, but on the W124 it's a brown line that connects to the large vacuum line that leaves the vacuum pump and goes into the brake booster. That vacuum line snakes around past the GP Relay, under the fusebox and into the firewall.

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-justin

1987 300TD, 1987 300TD
2008 R32, 2000 Passat Wagon

I'm most confused. The link I posted above brought up pages of info last night. Very strange.......

BTW, we have a very limited search function, and will only look up single words. You could put in vacuum leak, but you will get all things with vacuum, and all things with leak.......

Do a search on "shutoff" as key word, and search 'titles only' in box under that, and 'Diesel Discussion' as the forum....

__________________
Jimmy L.
'05 Acura TL 6MT
2001 ML430 My Spare

Gone:
'95 E300 188K "Batmobile" Texas Unfriendly Black
'85 300TD 235K "The Wagon" Texas Friendly White
'80 240D 154K "China" Scar engine installed
'81 300TD 240K "Smash"
'80 240D 230K "The Squash"
'81 240D 293K"Scar" Rear ended harder than Elton John

I would imagine there are several links for this issue in the stickys and DIY archive. Just a thought.

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1989 300E 144K

Diesel Injection:
http://www.peachparts.com/shopforum/showthread.php?t=142405

The first three links cover the topic.



Have a great day.

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1985 300SD
1983 300D
1984 190D
2003 Volvo V70
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Does anyone know what size lines the 300SD uses? I'm going to do what all the Saabers do and replace all the vacuum line with silicon lines. They don't degrade and won't blow off. They come in 4, 6 and 8 mm sizes.

If only everybody used meaningful titles, a technique like the above mentioned would work really, really good. Instead we have "Oh my", "leaky leaky gloopy gloppy", "check this out" and "what is this"

Well for the most part titles are a good thing to search on

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-justin

1987 300TD, 1987 300TD
2008 R32, 2000 Passat Wagon

You can get hard lines made out of silicon?

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-justin

1987 300TD, 1987 300TD
2008 R32, 2000 Passat Wagon

Probably not. I know on my 300SD a few of the hardlines are connected via vacuum hose. Aren't the vacuum lines connected to many of the internal pots just regular vacuum lines?