DR-23A Air Switching System

This test must be performed with engine at normal operating temperature.
1. Remove air cleaner. Disconnect switch/relief valve downstream air hose, then start the engine.
2. Air should flow from downstream air port, with engine coolant above 150°F, or 125°F on some 4-135/2.2L engines. If air flow is satisfactory, proceed to Test 24 for 4-97/1.6L engine, or Test 25 for 4-135/2.2L engine.
3. If air will not flow, proceed to Step B.