Chevrolet Montana P1629 Engine Trouble Code
What is Chevrolet Montana P1629?
The Chevrolet Montana 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 Chevrolet Montana
Owners of the Chevrolet Montana should be aware that P1629 can appear alongside oil consumption warnings. Low oil pressure caused by a worn PCV system lets crankcase vapour contaminate the mass air flow sensor, sending erroneous readings to the ECU.
Code Information
| Code Type: | OBD-II Powertrain (P) Trouble Code |
| System: | Powertrain |
| Vehicle: | Chevrolet Montana |
| Brand: | Chevrolet |
| Model: | Montana |
| Code: | P1629 |
P1629 Chevrolet Montana Symptoms
Check Engine Light
Illuminated Chevrolet Montana dashboard warning
Engine Stalling
Engine stops unexpectedly or misfires
Performance Issues
Reduced power or acceleration on the Chevrolet Montana
Starting Problems
Difficulty starting the engine
Poor Fuel Economy
Increased fuel consumption on the Chevrolet Montana
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 Chevrolet Montana 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:
Crankshaft position sensor signals the computer for precise ignition and fuel injection timing. Faulty sensors cause rough running and reduced efficiency. Modern vehicles enter limp mode and illuminate the check-engine light.
Technical Notes:
Parts or components should not be replaced based solely on P1629 DTC. Consult your vehicle service manual for proper diagnostic procedures, possible causes, and required testing before replacement.
Chevrolet Montana P1629 Repair Cost
Fuel injector cleaning service on the Chevrolet Montana costs $150–$300 for an ultrasonic bench-clean of all injectors with flow-test certification. On-car induction cleaning is a cheaper ($80–$120) first step but is less thorough for heavily fouled injectors.
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 Chevrolet Montana
When P1629 triggers on the Chevrolet Montana, 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 Chevrolet Montana
After any repair that involved disconnecting the battery on the Chevrolet Montana, the power window, steering angle sensor, and transmission adaptive values all require a reset drive cycle. Skipping this can cause false fault codes — including P1629 — for the first two to three start cycles.
Preventing P1629 on the Chevrolet Montana
The Chevrolet Montana coolant temperature sensor plays a role in fuel enrichment during warm-up. Replacing it as a precaution at 80,000 miles ($25–$40 DIY) prevents the faulty cold-start enrichment that can lead to P1629.
Frequently Asked Questions — Chevrolet Montana P1629
A: Not always. Across model years, Chevrolet revised sensor specifications, wiring paths, and ECU calibrations. Always confirm the repair procedure matches your specific vehicle's production year and engine code, as parts and labour times can vary significantly.