Celica Liftback L4-122 1998cc 2.0L DOHC Turbo (3S-GTE) (1992)
EGR Vacuum Modulator: Testing and Inspection
Fig. 36 EGR Vacuum Modulator Filters
1. Remove the top cap from vacuum modulator and check air filters for contamination or damage, Fig. 36. Replace filters if necessary.
2. Using compressed air, clean air filters.
3. Reinstall filters and top cap.
4. Disconnect the vacuum hoses from the ports of the EGR vacuum modulator.
Fig. 43 Testing Vacuum Modulator
Fig. 44 Testing Vacuum Modulator
5. Block one of the ports with your finger and blow air into the other port. Fig. 43
6. Air should pass through the air filter side of the vacuum modulator without resistance. If not as specified, replace the vacuum modulator.
7. Start the engine and maintain speed at 2,500 rpm.
8. Repeat step 2. There should be strong resistance to air flow through the filter, Fig. 44. If not, replace the vacuum modulator.
9. Reconnect vacuum hoses to their proper locations.