I misunderstood which plenum connecting tube you were talking about. The other tube (smaller diameter) that connects to the plenum ends at an EGR type valve located on the driver's side rear of the engine and accessed just a few inches below the black corrugated plastic Y-hose that connects to the driver's side of the secondary air pump to the secondary air valves. When I replaced that tube and EGR valve I had to remove the wiring harness (shown in the
Starter DIY) and the windshield cowling and then the corrugated plastic Y-hose which has round plastic push clamps identical to the one found on the large tube you disconnect from the driver's side of the plenum.