Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

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EGR Backpressure Transducer: Testing and Inspection

Fig. 11 Exploded view of EGR modulator:





1. Inspect filter for dirt or damage, Fig. 11. Clean filter using compressed air.
2. Remove EGR modulator and plug nozzle using finger. Blow air through another nozzle and check that air passes through filter side freely.
3. Connect a suitable vacuum pump gauge to nozzle 1, then plug nozzle 2 with finger. Blow air into nozzle 3, operate vacuum pump gauge and check that vacuum is applied to modulator.
4. Reconnect vacuum hoses.