Power Loss + Transmission "jumpy"

I just bought an '81 300SD turbodiesel (~200k miles) and the acceleration is slow and power is ridiculously low. I suspected the injector heads + fuel lines were dirty and built-up, so i did a diesel
purge (using lubroMoly) and replaced both fuel filters. Power or acceleration did not increase. Is this still an issue in the fuel lines, what should I look to next?
A linked issue --> as I need to floor the accelerator to go anywhere, the automatic transmission is really jumpy when shifting in between gears. I read somewhere about adjusting the accelerator modulator, but am unsure of exactly how to do this and what to set it too. Can anyone help with these issues?
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One thing at a time.
Let's get the motor going, then address the transmission.
Diesels don't jump off the line like gas engines. Expect 0 to 60 mph in about 13 - 15 seconds. That's when it was new with say 25,000 miles. We'll do the best we can with 200K miles. In the order of complexity and work:
1. Is the exhaust laying down a smoke screen? If so check the paper air filter element; it probably needs to be replaced.
2. Check the throttle linkage. Have a helper sit in the driver seat with the motor OFF and floor the throttle while YOU watch the movement of the throttle levers etc. especially the one that goes down behind the injection pump. The lever back there should touch the full throttle stop when the helper floors the pedal. If it doesn't adjust the twist rod near the firewall so that it does touch.
3. At the very aft end of the intake manifold, near the firewall you'll see a plastic tube attached to the manifold. With the engine OFF remove the (hollow) bolt that attaches that tube and clean it out with a paper clip wire, also clean the "banjo fitting" that the hollow bolt secures. Reattach them. Then follow that plastic tube to ensure it's connected to each fitting all the way to the injection pump. If not, fix the break.
4. When were the motor's valves last adjusted?? Due every 15K miles. If they're neglected the motor has less compression making starting harder, especially when the weather is cold, and less power. You can adjust them yourself, it's done with the motor OFF and cold, not hot. Takes some time and patience.
5. Look at the injection pump - at the place where the plastic tube from the intake manifold attaches. It's a square with a circle and an adjustment screw in its center. Does it look like someone tried to adjust it? (Pray they didn't.)
6. The turbocharger should put out about 10 psi boost at 4,000 rpm under load (driving). It has a pressure relief valve (wastegate) to ensure that pressure is not exceeded. Turbos last a long time so the turbo is probably OK.
Check these items and pose the next questions. Next post given an opinion whether or not anyone has messed about with this motor.
Transmission: Designed to shift hard at full throttle and softly at moderate throttle so it sounds like it's doing just what it should.
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I agree with banjo bolt... probably clogged and affected the turbo.
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Clean out the banjo bolt fitting. There's be a clear hose at the back of the engine stuck on a brass bard on the intake. It gets clogged with good and can't do its propler job of telling the IP to dump more fuel into the engine when the turbo is spun up resulting in great slowness.
Just clean it out and you should notice an instant and dramatic difference.
This is fairly common. If the hose is not attached you'll have a 100% non-turbo car.

http://articles.mbz.org/transmission /
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