Ok, so this has been a worsening thing over the past 24 hours. Yesterday when I left work, I noticed that my car would be idling roughly at traffic lights but was ok. This morning, same thing. This evening when I got off work, though, the car started ok but it took a while to get the rpms up. On the way home, it would idle really rough for a few seconds then die at traffic lights. I had to put the car in park and keep my foot lightly on the gas pedal at every light to keep it from dying.

Coolant is topped off on my car (did that this morning) and oil is a quart low, just topped off my diesel a couple days ago. To me it's acting like it's fuel-starved, but I changed both my fuel filters less than a year ago. I do use Marvel's Mystery Oil every now and then but not regularly.

Suggestions?

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1983 240D, 272K+ miles (odo broke)

If the Fuel is contaminated a new Fuel Filters can plug up in a matter of Minutes. However if you are not having a loss of power at higher speeds it is not likely the Filters.
The Marel Mstery Oil is a poor lubricant for the Fuel Injection Pump. It scored very low on a Test done by Spicer. 2% Biodiesel mixed with the Fuel did best and Diesel Kleen is somewhere up in the upper 1/3rd of the addatives and also has a Cetane Booster.

Back to your problem. Air Leaks in the Fuel Inlet Hoses. If you have the Old Style hand Primer with the shiny Aluminum Body they are a know source of Air Leaks; indication if you pump them and Fuel leaks out as you Pump.
Replace it with a Real Bosch one. Avoid Counterfeit ones that you might get on eBay.

On the Engine side of your Fuel Injection Pump there is what looks like a typical Banjo Bolt holding the Fuel Return Line onto the Fuel Injection Pump.
If it has a Ball Bearing pressed into the head of it all you can do is look for a replacement. If that Banjo Bolt has a plug that can screw out of it you can remove the Spring and the Ball Bearing inside that is the Valve.

Measure the Spring and if it is not 27mm long you are allowed to stretch it until you get a 27mm free length of the Spring.

You did not say if you were only useing Diesel Fuel or not?
The Fuel Supply/Lift Pumps on these Engines are getting old. The rebuild kits for them do not cost too much $30-$40 for the real Bosch complete kits.

More details on Parts and part numbers and rebuild:
DIY Repair Links
http://www.peachparts.com/shopforum/forumdisplay.php?f=82

http://www.peachparts.com/Wikka/DoItYourSelf

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84 300D, 82 Volvo 244Gl Diesel

I just use regular diesel fuel, no biodiesel. Been getting it from the exact same gas station for five years.

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1983 240D, 272K+ miles (odo broke)

You probably have an air leak as was said about, replace the filters, primer pump if it isn't the new black one and look for fuel leaks.

Have you adjusted your valves?

Motor/trans mounts ever been replace?

You may very well have more then one issue going on...

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Valves were last adjusted a year and a half ago, mounts were replaced when I first got the car (eight years ago).

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1983 240D, 272K+ miles (odo broke)

I suggest you treat the fuel with Biocide.

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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.

Is the power level fine otherwise (meaning the car is not slower then normal)? Look carefully at the linkages for the throttle control and the fuel shut off, something could be bent/binding or stuck forcing it down (as if you are trying to shut the engine off manually with the linkages under the hood). A spring could be broken or stop broken off (I have seen it before that is why I mention it).

When the car is under load it runs perfectly fine. Sometimes it's a little slow to accelerate from a stopped position but not all the time.

One new development: oil seems to be leaking out from under the oil cap. It was doing it a tiny bit when I checked the level a few days ago, but it was definitely noticeable when I was topping it off this morning. Could be unrelated, but I guess I gotta get a new gasket for the cap now.

Also, dunno if it's a fluke or not but it seems to idle slightly better when it's facing uphill.

ETA: Stupid guys at Autozone had no idea what I was talking about when I said I needed some biocide. What brand do you recommend?

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1983 240D, 272K+ miles (odo broke)

I normally use Startron when I need to make sure nothing is growing in the fuel. It has taken me from barely idling to smooth running a couple of times.

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85SD 240K & stopped counting painted, putting bac together. 84SD 180,000. sold to a neighbor and member here but I forget his handle. The 84 is much improved from when I had it. 85TD beginning to repair to DD status. Lots of stuff to do.

Diesel911 has given excellent suggestions. Start with simple/easy/cheap and work your way toward complex/expensive.

If you can see any black inside the clear fuel pre-filter, there is a very good chance your fuel tank has a microbial growth blooming, and you will need several sets of filters and biocide to get past it.

Biocide for diesel fuel is normally found at a marine goods store, like West Marine. Some truck stops may have it.

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Respectfully,
/s/
M. Dillon
'87 124.193 (300TD) "White Whale", ~392k miles, 3.5l IP fitted
'95 124.131 (E300) "Sapphire", 380k miles
'73 Balboa 20 "Sanctification"
Charleston SC

Possible kinked fuel hose? I recently replaced the fuel hoses in my car and one of the replacements was too long, causing it to kink and keep fuel from effectively getting to the engine, which resulted in performance much like what you describe.

Took a look at my clear pre-filter and well gee, there's the problem...



Also, my husband noted my alternator is slightly rotated. He's fixing that right now.

Should I go ahead and change my spin-on filter too since I gotta switch my clear one anyway?

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1983 240D, 272K+ miles (odo broke)

May as well and keep an eye on the new primary filter.

You may have a build up in the tank, using biocide will help dissolve the little critters and clean out the tank.

I use the stuff in the pic, pricey, but should last a lifetime. Picked up from the local marina.

Attached Thumbnails

 

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83 SD

84 CD

Could this just be due to a bad batch of diesel? The car was fine until I topped off the tank over the weekend. First time it's happened to me if it is.

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1983 240D, 272K+ miles (odo broke)

^ Yes.

Maybe use a cleaner/de-waterer type additive in the fuel.

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83 SD

84 CD