Throttle/Fuel Inhibit Circuit
The P2552 code means the vehicle's onboard diagnostic system has detected: Throttle/Fuel Inhibit Circuit. This is a critical severity code.
- Keep driving?
- No -- stop driving
- DIY difficulty
- hard
- Estimated cost
- $100 - $800 (parts and labor)
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Common Symptoms
- Engine will not rev above idle
- Throttle input completely ignored
- Multiple warning lights on
- Vehicle in emergency limp mode
Probable Causes (Ranked by Likelihood)
- Safety circuit activated due to detected fault Very High
- Wiring issue in throttle inhibit circuit High
- Failed throttle position sensor triggering inhibit Moderate
- ECM software fault activating inhibit erroneously Low
Step-by-Step Diagnostic Procedure
-
Scan for all stored codes that may have triggered inhibit
-
Check throttle inhibit circuit wiring and connectors
-
Test throttle position sensor signals
-
Clear codes and test if inhibit releases
Frequently Asked Questions
What is the throttle/fuel inhibit circuit?
It is a safety circuit that disables throttle and fuel delivery when the ECM detects a potentially dangerous fault, preventing unintended acceleration.
Why won't my engine rev above idle with P2552?
The inhibit circuit has been activated, intentionally limiting engine operation to idle for safety. Another fault code likely triggered this protective response.
Can I clear P2552 to restore normal operation?
Clearing codes may temporarily release the inhibit, but the underlying fault must be repaired. The code and limitation will return if the root cause is not fixed.
Sources
This page is built from documented references. Verify against your own service info before repair work.
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