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Home >> GMC >> 1990 >> Forward Control 3.9 L >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes - TBI >> Diagnostic Tests >> Code 35: Idle Speed Error (2.5L) >> PCV Valve
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PCV Valve

The wrong PCV valve may cause incorrect idle speed.

Fig 1: Code 35: Idle Speed Error (2.5L) Circuit Diagram
G90A18838
Fig 2: Code 35: Idle Speed Error (2.5L) Flow Chart
G90E13957