Hello, I've got a 1984 300D turbo diesel, 346,000 miles. Bought it last summer. It just started running rough recently (missing) and kind of sounds like maybe there is some back pressure? If it was gasoline, I'd replace the plugs, wires, and cap, and if that didn't fix it, see if the converter was clogged. However, since it's a diesel, my first, I'm lost. Some background: Last week the glow plug light started acting up and now won't come on. I assume that isn't related to my problem, don't the glow plugs only effect starting? I've read in this forum how to fix the glow plugs, just haven't done it yet. Replaced turbo and alternator 2 months ago. Last summer replaced both fuel filters, air filter, injector bypass hoses, oil change. I first noted a slight deep rumble sound at accel/decel around 20-40 mph. This reminded me of a pressure type sound if your exhaust is clogged. Now it has been running progressively rougher. Just seems to be "missing." Where should I start looking? Ran great prior, still goes down the road good at speed, no smoke.
Thanks for any help! Tom

Is it leaking fuel anywhere? Specifically around the injectors and/or the primer pump?

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2001 Dodge Ram 2500 Cummins Turbo Diesel - 4x4, auto, 3.54 gears, long bed
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'92 300D 2.5 Turbodiesel - sold
'83 300D Turbodiesel - 4 speed manual/2.88 diff - sold
'87 300D Turbodiesel - sold
'82 300D Turbodiesel - sold

I would try a valve adjustment, and maybe run a couple of bottles of diesel purge through the engine, Diesel Giant has tutorials on how to do both, and they are both pretty easy.

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^^Yes, sounds like air is getting in the fuel line somewhere.
You are correct, the glow plugs affect only starting.
I've heard back pressure is not an issue with these cars.

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83 SD

84 CD

I second a valve adjust as well. When was the last one done?

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RRGrassi


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