Go-Parts
Cart 0
Your cart is empty
Add an item to see it appear here.
Wrenchy
Go-Parts Garage
Expert guides for diagnosing, troubleshooting, and replacing auto parts Expert guides for diagnosing and replacing auto parts
Browse All Articles →
🎬 Helpful Videos 🛍️ Shop This Part

Chrysler TC Maserati 1989-1991 Oxygen Sensor Location and Replacement Guide

Fix poor fuel economy and rough idling on your TC by understanding and choosing the right oxygen sensor.

3 minutes to read 1989-1991 Chrysler TC Maserati
Difficulty
2/5
Est. Time
1 hrs
DIY Doable?
✅ Yes
Shop Labor
$75-$150
⚠️ Drivable, but... — Yes, but you will experience poor fuel economy and performance, and prolonged driving could damage your catalytic converter.
Key Takeaways
  • Your TC has a single, upstream heated oxygen sensor that is critical for fuel economy.
  • Choose a direct-fit sensor from a reputable brand like NGK/NTK or Denso for best results.
  • The most difficult part of the job is often removing the old sensor, which can be seized with rust.
  • A bad O2 sensor will trigger a 'Check Engine' light, with OBD-I code '21' being the most common indicator.
The oxygen sensor, or O2 sensor, on your 1989-1991 Chrysler TC by Maserati is a critical part of the emissions and engine management system. It is located in the exhaust system and measures the amount of unburned oxygen in the exhaust gas. This information is sent to the engine computer, which then adjusts the air-to-fuel ratio. A properly functioning sensor ensures the engine runs efficiently, maximizing fuel economy and minimizing harmful emissions. For the TC's early electronic fuel injection systems, whether the 2.2L turbo or the 3.0L V6, this sensor's input is vital for optimal performance.

Is Your TC's Oxygen Sensor Failing?

The oxygen sensor is a normal wear-and-tear item that typically lasts between 60,000 and 100,000 miles. On a classic vehicle like the TC, it's often an overlooked maintenance part. When it fails, the engine's computer receives incorrect data, leading to noticeable driving issues. These vehicles use a single upstream oxygen sensor (before the catalytic converter) which is essential for engine tuning. A failing sensor can cause the engine to run too rich, wasting fuel and potentially damaging the catalytic converter over time.

Choosing the Right Aftermarket Oxygen Sensor

Finding a new old stock (NOS) Mopar oxygen sensor for the TC is highly unlikely, making aftermarket brands the primary option. Fortunately, modern aftermarket sensors often meet or exceed the original 1980s technology. The most important factor is choosing a "direct-fit" model with the correct electrical connector to avoid cutting and splicing wires.

Aftermarket Brand Quality Tiers

TierBrandsAssessment
Tier 1 (Excellent)NGK/NTK, DensoWidely regarded as top-tier choices and are often the original equipment manufacturer (OEM) for many brands. They are known for precision, reliability, and are a preferred choice among many enthusiasts for Chrysler vehicles.
Tier 2 (Good)Bosch, DelphiBosch invented the modern oxygen sensor and is a trusted name. While their quality is generally high, some forum users note that aftermarket Bosch sensors can occasionally be less consistent than their OEM parts or Tier 1 brands on certain vehicles. Delphi is a reputable OEM supplier with a solid track record.
Tier 3 (Standard)Walker Products, DriveWireWalker is a well-known exhaust and emissions parts manufacturer that offers a balance of affordability and performance. Some users report good experiences, while others have noted a shorter lifespan compared to premium brands. DriveWire is typically a budget-friendly option.

Known Issues, Recalls, and Service Bulletins

A search of the National Highway Traffic Safety Administration (NHTSA) database and other public records found no specific recalls or Technical Service Bulletins (TSBs) for the oxygen sensor on the 1989-1991 Chrysler TC Maserati. However, owners on forums frequently discuss the challenges of replacing the original sensor, which often becomes seized in the exhaust pipe due to age and heat cycles. Applying a good quality penetrating oil and, in some cases, heat is often necessary for removal.

🎬 Watch this guide on troubleshooting and replacing your oxygen sensor.

Cost of Replacing an Oxygen Sensor

The cost will vary based on the brand you choose and whether you perform the labor yourself.

Estimated Costs

New Aftermarket Part$46.18 - $85.17
Shop Labor$75 - $150

Frequently Asked Questions (FAQ)

How many oxygen sensors does my 1989-1991 TC have?

Your Chrysler TC Maserati is equipped with one upstream oxygen sensor. Vehicles from this era use an OBD-I system and do not have a second, downstream sensor after the catalytic converter.

🎬 Learn more about O2 sensor locations and numbering systems.
Where is the oxygen sensor located?

The single sensor is located "upstream," meaning it is screwed into the exhaust pipe or exhaust manifold before the catalytic converter. On 2.2L turbo models, it is often in the turbo outlet housing. Access can be challenging, with some owners finding it easier to reach from underneath the vehicle.

Is this a heated or unheated oxygen sensor?

The 1989-1991 TC uses a heated oxygen sensor, which will have 3 or 4 wires. Heated sensors come up to operating temperature faster, allowing the engine computer to enter its efficient "closed-loop" mode sooner. It is important to verify if your specific vehicle has a 3-wire or 4-wire sensor before ordering a replacement.

Can I clean my old oxygen sensor instead of replacing it?

While some attempt to clean O2 sensors, it is not a reliable or recommended long-term solution. The internal sensing elements degrade over time and cannot be restored by cleaning the exterior. Given the affordable cost of a new sensor, replacement is the best course of action.

O2 SENSOR LOCATIONS, BANK NUMBERS, SENSOR NUMBERS, UP AND DOWN STREAM: AN EXPLANATION
O2 SENSOR LOCATIONS, BANK NUMBERS, SENSOR NUMBERS, UP AND DOWN STREAM: AN EXPLANATION
How to Troubleshoot and Replace an Oxygen (O2) Sensor
How to Troubleshoot and Replace an Oxygen (O2) Sensor

Technical Specifications

Location: Upstream (before catalytic converter). Type: Heated (3 or 4-wire). Thread Size: M18-1.50.

Wrenchy
Article researched & written by
Go-Parts' AI research assistant. Every article is backed by live web research, verified OEM data, and real technician knowledge — so you get accurate, up-to-date information you can trust.
Meet Wrenchy → Updated Mar 31, 2026

The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.

Year Coverage
This article covers the Oxygen Sensor for:
  • Chrysler TC Maserati: 198919901991
In this article
🎬 Helpful Videos
Jump to ▴

Email This Guide

We'll send you a link to this article so you can read it later or share it.

Added to cart · Part