p0491
Moderate
Porsche · SUVs
Secondary Air Injection System Insufficient Flow (Bank 1)
Quick Answer
Error code P0491 on your Porsche SUVs means: Secondary Air Injection System Insufficient Flow (Bank 1). This is usually fixable — see the step-by-step guide below.
Affected Models
Likely Causes
How to Fix It
1
Check secondary air pump operation
2
Inspect air injection hoses for blockage
3
Test air check valve function
4
Verify pump relay and fuse status
Pro Tip
This fix requires some technical knowledge. If you're unsure about any step, consider contacting support or a qualified technician.
Parts You May Need
Secondary air pump
Air check valve
Injection hoses
Relay and fuse
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