Intake Manifold Tuning Valve Control Circuit/Open Bank 1
The P0660 code indicates a problem with the intake manifold tuning valve control circuit for bank 1. This valve adjusts the intake runner length to optimize engine performance across different RPM ranges. The PCM detects an open or short circuit in the control circuit, preventing proper valve operation.
01. Most Common Causes
- Faulty intake manifold tuning valve
- Open or shorted wiring in the control circuit
- Corroded or damaged connector
- Failed PCM (rare)
02. Symptoms You Will Notice
- Check Engine Light on
- Reduced engine power or hesitation
- Poor fuel economy
- Rough idle or stalling
03. Step-by-Step Diagnosis
Step 1: Scan for codes and verify P0660 is present.
Step 2: Visually inspect the intake manifold tuning valve connector and wiring for damage or corrosion.
Step 3: Test the valve resistance with a multimeter (specs vary by vehicle).
Step 4: Check for voltage and ground at the valve connector with the engine running.
Step 5: If wiring and valve are okay, test PCM output or replace PCM.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is generally safe for short distances, but reduced performance and fuel economy may occur. Prolonged driving could cause further issues.
How much does it cost to fix?▼
Repair costs range from $50 to $150 for DIY parts, or $150-$400 at a shop, depending on the cause.