Toyota 4-Runner 1985 Repair Manual page 110

EC-10
VTV
EMISSION CONTROL SYSTEMS (EFI) - Dash Pot (DP) System
Filter
EC0198
EC010l
IF NO PROBLEM IS FOUND WITH THIS INSPECTION, THE
SYSTEM IS OKAY; OTHERWISE INSPECT EACH PART
INSPECTION OF VTV
1. CHECK AND CLEAN FILTER ON VTV
(a) Check the filter for contamination or damage.
(b) Using compressed air, clean the filter.
2. CHECK VTV BY BLOWING AIR INTO EACH SIDE
(a) Check that air flows without resistance from B to A.
(b) Check that air flows with difficulty from A to B.