09/07/2026 6:12 am
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P0016 with slow intake-cam response: oil-control fault or stretched timing chain?
Review the evidence, add a focused answer, and distinguish confirmed measurements from assumptions.
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A 2012 Equinox 2.4 sets P0016 after warm-up. Oil level and viscosity are correct. Commanding the intake cam shows actual angle moving slowly and stopping about 9 degrees short, while the exhaust cam follows command. The intake solenoid screen is clean and its current waveform is consistent with the exhaust solenoid.
What evidence should be collected before opening the timing cover?
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10/07/2026 7:48 am
Verify base oil pressure and compare cam response with the control solenoids swapped only if the parts and procedure allow it. Scope crank and both cam signals at a known reference condition and compare the pattern with service information. A mechanical offset that remains when control is neutral points toward chain, guide or phaser position rather than a command fault.
Also inspect for debris at the actuator and confirm the learned or desired positions are valid. Do not infer chain stretch from code text alone; the correlation waveform and mechanical inspection should agree.
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11/07/2026 7:50 am
The intake delay remained after the solenoid comparison. Crank-to-intake-cam correlation was shifted while the exhaust reference was correct. Inspection found an extended tensioner and worn guide. After timing-set service, both cams tracked command within 2 degrees and P0016 stayed cleared.