1500-1800rpm, light load, tap from engine, irregular, off throttle or more throttle it goes away, never notice unless the window is down and you try to hear it. No other odd symptoms, probibly been doing it for ages. Loose valve? T-chain/guide? Valve adjustment not long ago, probibly on the tight side still if I had to guess. Quick thoughts? Please don't hit me for not searching, it's hard to search for "tap" or "rattle" on a diesel forum when you don't have fifteen hours to spend reading.

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One more Radar Lover gone...
1982 VW Caddy diesel 406K 1.9L AAZ
1994 E320 195K

Sounds like light 'nailing' or a loose valve.

My wagon, sedan and 240 have all done the same thing at one time or another. May be a slightly worn injector causing some strangeness at light throttle loads.

Drive it.

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Never a dull moment at Berry Hill Farm.

You might try using a stethescope to find if it seems to be ' higher' or ' lower' on the engine, 'front' or 'rear'... that sort of general thing.. might help....

That's about what I was thinking. I'll try and check the valves this weekend. Trouble is with locating it is it will ONLY do it when in motion, sounds just perfectly normal at idle or free reving.

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One more Radar Lover gone...
1982 VW Caddy diesel 406K 1.9L AAZ
1994 E320 195K

If you decide to use the stethescope while someone else drives the car around... will you please have someone take pictures ?

Why of course..

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One more Radar Lover gone...
1982 VW Caddy diesel 406K 1.9L AAZ
1994 E320 195K

Kind of like this?

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DJ


84 300D Turbodiesel 190K with 4 speed manual sold in 03/2012