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Home >> Pontiac >> 1993 >> Firebird Formula, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes - 5.7L >> ECM/Pcm Code Charts >> Code 26 - Quad-Driver No. 1 Error >> Diagnostic Aids
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Diagnostic Aids

Engine should be idling while monitoring QDM status. Using scan tester, monitor QDM status while moving related harness connectors, including ECM harness. If the failure is induced, a fault will status while moving related harness connectors, including ECM harness. If the failure is induced, a fault will appear on scan tester. This can help to isolate intermittent problems. If code persists with no apparent problems, replace ECM.

Fig 1: Code 26 Schematic (5.7L "F" Body) Quad-Driver No. 1 Error
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Fig 2: Code 26 Flow Chart (5.7L "F" Body) Quad-Driver No. 1 Error
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