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

Choosing the Right Oxygen Sensor for Your 1987-1991 Ford F-150

Fix poor gas mileage and a rough idle by picking the correct new aftermarket oxygen sensor for your classic Ford truck.

4 minutes to read 1987-1991 Ford F-150
Difficulty
2/5
Est. Time
0.75 hrs
DIY Doable?
✅ Yes
Shop Labor
$75-$150
⚠️ Drivable, but... — Driving is possible, but it will cause poor fuel economy and could eventually damage your catalytic converter.
Key Takeaways
  • Your 1987-1991 F-150 likely has only one upstream oxygen sensor, making replacement simple and affordable.
  • Symptoms of failure include poor gas mileage, rough idle, and a rotten egg smell from the exhaust.
  • For best results, choose a sensor from an OE-equivalent brand like NGK/NTK, Denso, or Bosch.
  • Ignoring a bad O2 sensor can lead to a damaged catalytic converter, a much more expensive repair.
The oxygen sensor, or O2 sensor, on your 1987-1991 Ford F-150 is a key part of the engine management system. It sits in the exhaust and measures the amount of unburned oxygen leaving the engine. This information is sent to the truck's computer, which then adjusts the air-to-fuel ratio for the best performance and efficiency. A properly working sensor helps your truck run smoothly, burn fuel efficiently, and keep emissions low. Since these trucks are from the pre-OBD-II era, they typically have just one upstream oxygen sensor located in the exhaust before the catalytic converter.

Is Your F-150's Oxygen Sensor Failing?

An oxygen sensor won't last forever, and a bad one can cause real problems for your truck. If your F-150 is running rough, getting bad gas mileage, or smells like rotten eggs from the exhaust, the O2 sensor is a likely suspect. Because these sensors get lazy over time, you might not even get a check engine light, but you'll notice the poor performance and extra stops at the gas station.

🎬 Watch: Learn more about common symptoms of a bad sensor.

Common Symptoms of a Bad O2 Sensor:

  • Noticeably worse fuel economy
  • Rough or shaky idle
  • Sluggish acceleration and loss of power
  • Black smoke or a rotten egg smell from the tailpipe
  • Failing an emissions test

Choosing the Right Aftermarket Brand

When it comes to electronic parts on these Ford trucks, not all brands are created equal. While an OEM Motorcraft part is always a safe bet, several aftermarket brands offer excellent quality and value. Sticking with a reputable brand is important, as cheap, no-name sensors can fail quickly or be inaccurate right out of the box.

Brand Quality Tiers

Based on owner experiences and mechanic recommendations, here’s how the available brands generally stack up for your F-150:

  • Premium / OE-Equivalent (Best Choice): Brands like NGK (also known as NTK) and Denso are often the original equipment manufacturers for Ford and other automakers. They are widely considered the most reliable and long-lasting aftermarket choice. Bosch also invented the oxygen sensor and is a major OEM supplier, making it a top-tier option as well.
  • Quality Aftermarket: Delphi and Spectra are established brands that produce reliable sensors. They are a solid choice if you're looking for a good balance between price and quality.
  • Standard / Economy: Brands like Walker Products and DriveWire offer a budget-friendly option. While they can get the job done, some mechanics report a higher chance of early failure compared to premium brands. They can be a good choice for a quick fix, but may not have the longevity of the others.
Pro Tip: Many owners and mechanics recommend sticking with NGK/NTK or Denso for the best results and to avoid having to do the job twice.

Cost of Replacing Your Oxygen Sensor

Replacing the oxygen sensor on a 1987-1991 F-150 is one of the more affordable repairs you can make. The part itself is not expensive, and labor is minimal. Here is a general breakdown of what you can expect to pay:

Item Estimated Cost
New Aftermarket Sensor $34.81 - $74.81
New OEM (Motorcraft) Sensor $58 - $95
Shop Labor $75 - $150
Total Professional Replacement $110 - $225

Frequently Asked Questions

How many oxygen sensors does my 1987-1991 F-150 have?

Your truck almost certainly has only one oxygen sensor. It is located "upstream," meaning it's in the exhaust pipe between the engine and the catalytic converter. Later model trucks (mid-90s and newer) have multiple sensors, but your generation keeps it simple.

Is this a difficult job to do myself?

No, this is a great DIY job for beginners. 🎬 See this step-by-step walkthrough for replacing your F-150 sensor. The sensor is usually easy to access on the exhaust pipe underneath the truck. The main challenge is that the old sensor can be rusted in place. Spraying it with penetrating oil beforehand and using a special O2 sensor socket (which you can often rent from an auto parts store) makes the job much easier.

Can I just clean my old oxygen sensor?

While some people attempt to clean O2 sensors, it is not recommended and is rarely effective. The sensing element inside becomes contaminated or simply wears out over its 50,000-100,000 mile lifespan. Given the low cost of a new sensor, replacement is the only reliable solution.

What happens if I don't replace a bad O2 sensor?

You can continue driving, but it's not a good idea. Your engine will run inefficiently, wasting a lot of gas. More seriously, running too rich (too much fuel) for a long time can dump unburnt fuel into your exhaust, which can overheat and destroy your catalytic converter—a much more expensive part to replace.

Do I need a heated or unheated sensor?

Most 1987-1991 F-150s use a 3-wire or 4-wire heated oxygen sensor. The heater brings the sensor up to operating temperature quickly, which improves accuracy when the engine is cold. Always check the connector and wire count on your old sensor to ensure you buy the correct replacement. 🎬 Watch: How to use Forscan for troubleshooting your oxygen sensor. Using the wrong type can cause performance issues.

How to Replace O2 Oxygen Sensor 1990-2010 Ford F-150 Truck
How to Replace O2 Oxygen Sensor 1990-2010 Ford F-150 Truck
Ford F150 O2 Up/Down Stream Sensor Replacement Made Easy
Ford F150 O2 Up/Down Stream Sensor Replacement Made Easy
SYMPTOMS OF A BAD OXYGEN SENSOR
SYMPTOMS OF A BAD OXYGEN SENSOR
Symptoms of a Bad O2 Sensor
Symptoms of a Bad O2 Sensor
Oxygen sensor replacement ford f150 using forscan troubleshooting
Oxygen sensor replacement ford f150 using forscan troubleshooting

Technical Specifications

OEM Part Numbers: E7TZ-9F472-A F1UZ-9F472-A GU2Z-9G444-A

Most models from this period use a 3-wire or 4-wire heated oxygen sensor with a threaded M18x1.5 body. The wrench size is typically 22mm (7/8"). Always verify the wire count and connector shape against your original part.

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 Apr 19, 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:
  • Ford F-150: 19871988198919901991
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