I've posted this before but didn't get any clear answers so I'm trying again in the hopes someone has come across this since.

P0410 is reason for MIL.

Here is what I found after digging into the system;
1) air pump is fine, blows strong at start-up
2) vacuum solenoid works fine, vacuum at both check-valves & both check-valves work fine
3) O2 sensor seems to be functioning as it should.
4) R&R'd both check-valves and both ports into the head were clogged with black crud.
5) picked out crud w/a small jewelers screwdriver then blew out resultant crumbly bits w/compressed air
6) Sprayed MAF cleaner down ports
7) Port on driver's side (lft) seems to be clear
8) Port on passenger side (rt) remains clogged deeper down, currently has MAF cleaner soaking in it
9) spun crank, no change, MAF cleaner remains at the same level in the port

QUESTIONS REMAINING:
1) can I clear the clog with something long & flexible?
2) planning on letting the port soak overnight then trying to blow it out with compressed air, any reason I should not attempt this?

__________________
1999 E320 (gave to daughter) 250K
1994 F150 (may be the end of its road) 240K
1989 560 SL (Reassembly after paint job) 160K
1986 560 SL (deceased., gave it's life protecting my wife)
1988 300 TE (departed)
1994 945T (still running strong with an upgraded cam) 349K
1986 242Ti (deceased)
1968 GT500KR (under restoration)