Hello. Ok so the car is in park. I step on the gas, the car revs up and then without removing or moving my foot it goes right back down to idle... This happens while I still have my foot on the gas. If I step on it again, it'll rev up but eventually it'll come back down. What could be the problem? This happens while I'm driving too. The car has great pick up when I'm on the freeway though.

Digieditny

Have you checked for excessive play in your throttle linkages?

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Current Mercedes
1979 maple yellow 240D 4-speed

Gone and fondly remembered:
1980 orient red 240D 4-speed

Gone and NOT fondly remembered:
1982 Chna Blue 300TD

Other car in the stable:
2013 VW Jetta Sportwagen TDI / 6-speed MT

No. I just got this car on saturday and am completely new to mercedes benz and diesels... Is there a tutorial somewhere I can look at?

digi

have someone step on the throttle while you look at the linkage as it moves. odds are good you will see what is wrong if it's linkage related. likely the bolts that hold the swivel parts to the valve cover are loose.
if everything moves smoothly, and it does not look like things are broken, post back.

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

I'll do this tomorrow morning and get back. Do I do this with the engine running? Link to what the linkage looks like? I'll do a bit of searching.

digi

With the engine off!

Once the helper "floors" it, grab the linkage under the hood and see if you can move it more in the "go" direction.

Super-standard with a new-to-me '80s diesel MB car is to pop ALL the linkage balls loose, clean them, then lube with a drop of ATF (stone age, yes, but MB spec).

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James Marriott
2003 Buick Regal
1983 300D (228k, frau Auto)
1996 Suburban K2500 (192k, 6.5 turbo diesel/4WD towmaster 10,000)
www.engineeringworks.biz
1987 300SDL junker 170k
1982 300SD junker, 265k

After my helper floored it, I was able to pull it in the go direction about half an inch. Would that need adjustment? If so, what exactly do I adjust?

Digi

Full travel at the go pedal should result in full travel of the arm at the other extreme of the linkage the go lever on the injector pump.

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CC: NSA

All things are burning, know this and be released.

82 Benz 240 D, Kuan Yin
12 Ford Escape 4wd

You're four times

It's hard to

more likely to

concentrate on

have an accident

two things

when you're on

at the same time.

a cell phone.

www.kiva.org It's not like there's anything wrong with feeling good, is there?

There is a bunch of info in the Factory Service Manual about adjusting the throttle.

Available here: http://www.classictechlit.mbusa.com/MB/cstmsearch.asp?MYID=1038&SDID=1297&MDID=1168&ENID=1156&catalog_name=Retail

I recommend getting a copy, cheap too.

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83 SD

84 CD

it could need the coupling on the pedal replaced, or the swivel on the firewall replaced.
take a picture for us.

K I will take a pic in a few minutes.

Most common throttle linkage failure is the bushing on the firewall:

throttle pivot broken

__________________
'85 300TD "Puff The Magic Wagon" - Rolling Resto
'19 Mazda CX-9 Signature - Wife's sled
'21 Morgan 3-Wheeler P101 Edition
'95 E300d - SOLD
'84 300TD "Brown Betty" - Miss this one
'81 240D "China Baby" - Farm grocery getter

Here are some pictures of the linkage. How does everything look? I haven't adjusted anything. I just installed a new primary fuel filter.

Man I never noticed all the rust till I took these photos. OUCH!

digi

Attached Thumbnails

     

Oh I also wanted to say that after installing the new fuel filter, the car felt peppier but it still didn't hold power. Pushed the pedal and the rpms go up but then eventually back down without moving my foot. The car idles kinda rough. Thought it was gonna shut down on me

digi

Does the engine behave the same way if instead of pushing the accelerator, you grab the linkage near the IP and open it up all the way. If it still behaves the same way, you could probably exclude a linkage problem.

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13