Air and Fuel› Oxygen Sensors, Controllers and Components

ACDelco

Heated Oxygen Sensor

$121.54

SKU: AFS74

In Stock
In Stock
Ships by Sep 12
Free Shipping over $200
$100 Minimum Order
30 Days Return
INSTALL DIFFICULTY
DIY PRO SHOP

Easy — 1–2 hours

Overview

The ACDelco AFS74 is a heated oxygen sensor designed to be a GM-recommended replacement for your vehicle's original component. It functions as a feedback sensor on your vehicle's exhaust system, measuring the proportion of oxygen in the exhaust gases. This measurement allows the engine management computer to adjust the air/fuel ratio for optimal engine performance, emissions, and fuel economy.
Show original supplier description
The ACDelco AFS74 oxygen (O2) sensor is a GM Genuine part, offering a direct replacement for your vehicle's original component. As a special feedback sensor integrated into the exhaust system, it precisely measures oxygen levels in the exhaust gases. This critical data enables the engine management computer to fine-tune the air/fuel mixture to the ideal ratio of 14.7:1, thereby optimizing engine performance, minimizing emissions, and maximizing fuel economy. Manufactured to GM OE specifications, this heated oxygen sensor ensures fit, form, and function comparable to the original equipment. It features a threaded mounting type with an M18x1.5 thread size and a 0.71-inch thread diameter, along with a 349.5 mm (13.74 inch) overall length and a 252 mm (9.92 inch) wiring harness. The sensor itself has an oval connector shape and three male terminals. Proper functioning of the O2 sensor is vital for engine efficiency. However, these sensors can fail due to contamination from various sources. Common contaminants include antifreeze, silicone sealants, and carbon buildup. Issues like cracked cylinder heads, leaking head gaskets, clogged air filters, or defective fuel injectors can lead to sensor contamination and premature failure. It is recommended to visually inspect the sensor for signs of contamination and address any underlying issues before replacing the sensor to ensure longevity.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

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Specifications

BrandACDelco
Part NumberAFS74
CategoryAir and Fuel

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Returns & Fitment

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

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