Inspect the manifold EGR (A) ports and the EGR inlet and outlet pipe for blockage caused by excessive deposits or other damage. Was the problem found? YES – Correct the condition as necessary. NO – Go to step 18. Connect the hand vacuum pump (with gauge) to the EGR valve. Apply 26 kPa (200 mm Hg, 7.9 in. Hg) of vacuum with hand vacuum pump. Did the EGR valve work properly? YES – Substitute a known good ECM and recheck. If symptom/indication goes away, replace the original ECM. NO – Replace the EGR valve.

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