From smooth idle to convulsions, then back...

83, K-20 6.2l diesel, 3-sp manual.
Any tips to where to look for trouble. I figure if it was a rod or bearings the symptom would not be intermit.

--
Just recently it started to go into convulsions for a few seconds then
return back to a smooth idle.
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I wouldn't think it's the timing chain, that just causes shitty everything (in gas engines) and seeing how timing is even more important in diesel... I'm wondering if diesels have EGRs? Thats what it sounds like to me...
Change the cap, rotor, plugs, and wires, and get back to us :0)
-The Lonely Grease Monkey 1985' K5 305CUI TH700R4 NP208 KJ's successor
"Ignorance is preferable to error; and he is less remote from the truth who believes nothing, then he who believes what is a wrong." - Thomas Jefferson
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.