P1891 Buick Code - Throttle Position Sensor PWM Signal Low
Quick Answer
P1891 Buick indicates Throttle Position Sensor PWM Signal Low. Common causes include Faulty Throttle Position Sensor, Throttle Position Sensor harness is open or shorted, Throttle Position Sensor circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P1891 Buick indicates Throttle Position Sensor PWM Signal Low.
- Common causes
- Common causes include Faulty Throttle Position Sensor, Throttle Position Sensor harness is open or shorted, Throttle Position Sensor circuit poor electrical connection.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Code P1891 Buick Description
What are the Possible Causes of the DTC P1891 Buick?
- Faulty Throttle Position Sensor
- Throttle Position Sensor harness is open or shorted
- Throttle Position Sensor circuit poor electrical connection
How to Fix the DTC P1891 Buick?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P1891 Buick code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
Need more information about the P1891 Buick code?
Need more information on how to fix the P1891 Buick code? Get Access to Factory Service Manuals
Need Help with the Code?
Get the P1891 Buick code diagnosed by a professional: Find a repair shop in your area
Frequently Asked Questions about P1891 Buick Code
1. What does the OBDII code P1891 mean on a Buick?
P1891 indicates that the Throttle Position Sensor (TPS) is detecting a low Pulse Width Modulation (PWM) signal, which suggests an issue with the TPS circuit or its functionality.
2. What are the common symptoms of a P1891 code on a Buick?
Symptoms may include poor acceleration, reduced engine performance, erratic idling, or the illumination of the check engine light.
3. What causes the P1891 code on a Buick?
Common causes include a faulty throttle position sensor, damaged wiring or connectors in the TPS circuit, or issues with the engine control module (ECM).
4. Can I drive my Buick with a P1891 code?
While the car may still be drivable, it could experience reduced performance and unsafe driving conditions. It’s best to address the issue promptly.
5. How do I diagnose the P1891 code on a Buick?
Start by checking the TPS and its wiring for damage or corrosion. Use a multimeter to test the TPS voltage and inspect the ECM for potential faults.
6. What repairs can fix the P1891 code on a Buick?
Repairs may include replacing the throttle position sensor, repairing or replacing damaged wiring, or reprogramming or replacing the ECM.
7. How much does it cost to fix the P1891 code on a Buick?
Repair costs depend on the issue. Replacing a TPS typically costs $100–$300, while ECM repairs or replacements can cost $500–$1,200.
8. Can a dirty throttle body cause the P1891 code?
Yes, a dirty or clogged throttle body can interfere with the TPS readings and trigger the code. Cleaning it may help resolve the issue.
9. Is the P1891 code specific to Buick vehicles?
No, the P1891 code can appear on other vehicles with similar systems, but its exact meaning and diagnosis steps may vary by manufacturer.
10. Will resetting the check engine light fix the P1891 code?
Resetting the light will clear the code temporarily, but the underlying issue must be fixed to prevent the code from returning.
Discuss the causes and fixes for P1891 Buick OBDII Code
Code P1891 Buick comments
No comments found for this page.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.
