Renault Twingo P1629 Engine Trouble Code
What is Renault Twingo P1629?
The Renault Twingo P1629 check-engine light can indicate issues ranging from minor (loose gas cap) to serious (catalytic converter failure). Professional diagnostic scanning at a dealer or shop will identify the exact cause and required repairs.
P1629 on the Renault Twingo
Independent workshop data shows that Renault Twingo vehicles with P1629 resolve approximately 40% of cases after a throttle body cleaning and idle relearn procedure. This is always the recommended first step before investing in new sensors.
Code Information
| Code Type: | OBD-II Powertrain (P) Trouble Code |
| System: | Powertrain |
| Vehicle: | Renault Twingo |
| Brand: | Renault |
| Model: | Twingo |
| Code: | P1629 |
P1629 Renault Twingo Symptoms
Check Engine Light
Illuminated Renault Twingo dashboard warning
Engine Stalling
Engine stops unexpectedly or misfires
Performance Issues
Reduced power or acceleration on the Renault Twingo
Starting Problems
Difficulty starting the engine
Poor Fuel Economy
Increased fuel consumption on the Renault Twingo
Increased Emissions
Failed emissions test due to P1629
P1629 Code Structure
Understanding what each digit means in the P1629 powertrain trouble code:
| P | 1 | 6 | 2 | 9 |
|---|---|---|---|---|
| Powertrain Code | Fuel And Air Metering | Fuel Temperature Sensor B Circuit Range/Performance | Turbocharger Boost Sensor A Circuit Low | Reverse Input Circuit |
How to Fix Renault Twingo P1629
Diagnostic Steps:
Check if fuel pump primes when key is turned to ON. Measure fuel pressure and verify bright white-blue spark at all plugs. Also verify mechanical timing alignment.
Repair Solution:
Most manufacturers number cylinders sequentially from front to back. Ford V-engines start with cylinder 1 at front left. In V-6 engines, cylinder 4 is front right; in V-8 engines, cylinder 5 occupies that position.
Technical Notes:
For P1629, verify VCT solenoid operation. Look for stuck or sticking valves caused by contamination. Consult vehicle-specific repair manual for proper component testing procedures.
Renault Twingo P1629 Repair Cost
A complete diagnostic health-check on the Renault Twingo before committing to any single repair costs $120–$180 at a dealership with live-data capability. This investment pays for itself if it prevents unnecessary part replacement, which is the single most common mistake when diagnosing P1629.
P1629 Description
P1629 engine trouble code is related to Reverse Input Circuit.
Main Cause
The primary reason for P1629 OBD-II Engine Trouble Code is: Fuel Temperature Sensor B Circuit Range/Performance.
Common P1629 Misdiagnosis on the Renault Twingo
When P1629 triggers on the Renault Twingo, a flashing check-engine light (as opposed to a steady one) indicates an active misfire. Misfire codes are commonly misdiagnosed as sensor faults; always rule out ignition and fuel delivery issues before testing sensors.
DIY Repair Guide: P1629 on Renault Twingo
Replacing the oxygen sensor on the Renault Twingo requires an O2 sensor socket (22mm or 7/8") and penetrating oil applied 24 hours in advance. On vehicles over five years old, the sensor threads often corrode into the bung; heat from a propane torch (briefly applied) is usually sufficient to free them.
Preventing P1629 on the Renault Twingo
Keeping the Renault Twingo battery in good health — testing specific gravity annually and replacing at first sign of degradation — protects the ECU voltage supply. Voltage drops during cranking cause sensor reading spikes that can spuriously store P1629.
Frequently Asked Questions — Renault Twingo P1629
A: Yes. Some fault conditions, particularly those involving EVAP system leaks or marginal sensor readings, store codes without producing noticeable drivability symptoms. These are called memory faults and still need to be addressed because they will eventually cause performance issues.