88 240 DL V-6 Running problem

I have an 88 ( I think) 240 with the V-6 engine. Found that if I manuelly hold the flapper valve open just a little it will idle. Once I let go it will immediatly die. I know there is an adjustment for this, and of course a set clearance, could anyone please help me. Also car has sat for a while, what grade oil is recommended. Also is it "normal" to here the lifters tapping ( are they hydraulic or solid lifters?). The tank fuel pump has been replaced and the main is working fine, allittle noisy. One other question, what is that canister next to the main fuel pump? Fuel filter?

This that that Peugeot Engine...that wasn't a success story. Check the MAF (sp?) sensor on the intake after the Box. It may be bad. Mine was and it caused the same problem...2.3L though. The sensor is like $300 new so go find it used in the local junkyard or Autozone