Test Description
WARNING: This page is about a different variant/trim than selected.
NOTE:
Test numbers refer to numbers on diagnostic chart.
- Plugged Intake Passage - Shut off engine, and remove EGR valve. Plug exhaust side port using a shop rag or suitable plug. Attempt to start engine. If engine runs at a very high idle (up to 3000 RPM is possible) or if engine starts and stalls, EGR intake passage is not plugged. If vehicle starts and idles normally, intake side passage is plugged. Plugged Exhaust Passage With EGR valve removed, plug intake manifold side passage using a suitable plug. Start engine and listen for exhaust noise. If no exhaust gas escapes from open EGR port, exhaust passage is plugged.
- Using Tech 1 tester, EGR solenoid should energize and allow vacuum to be applied to gauge. Vacuum at gauge may or may not slowly bleed off; however, gauge is able to read amount of vacuum being applied.
- Upon exiting field service mode, gauge vacuum should bleed off through a vent in solenoid. Pump gauge vacuum may or may not bleed off; this does not indicate a problem.
- Remaining tests check ability of EGR valve to interact with exhaust system. This system uses a negative backpressure EGR valve which will hold vacuum with engine off.
- When engine is started, exhaust backpressure at base of EGR valve should open valve's internal bleed. This will vent applied vacuum, allowing valve to seat.