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 →
🛍️ Shop This Part

GMC C1500 (1994-1999) Engine Intake Manifold Temperature Sensor Guide

Is your truck running rough or getting bad gas mileage? Your intake air temperature sensor could be the problem.

3 minutes to read 1994-1999 GMC C1500
Difficulty
1/5
Est. Time
0.25 hrs
DIY Doable?
✅ Yes
Shop Labor
$50-$100
⚠️ Drivable, but... — Yes, but you should get it fixed soon to avoid poor fuel economy and potential long-term engine issues.
Key Takeaways
  • A bad IAT sensor commonly causes poor gas mileage and a rough idle.
  • This is a very easy and cheap part to replace yourself, often requiring no tools.
  • For this part, a quality aftermarket brand like Standard Ignition is a cost-effective alternative to OEM.
  • A Check Engine Light with codes P0112 or P0113 points directly to this sensor.
The Engine Intake Manifold Temperature Sensor, often called the Intake Air Temperature (IAT) sensor, measures the temperature of the air going into your GMC C1500's engine. The engine's computer uses this information to get the right mix of air and fuel. Cold air is denser than warm air, so the computer adjusts the fuel and ignition timing based on the sensor's readings. This helps your truck run efficiently, get good gas mileage, and pass emissions tests.

Is Your Truck Trying to Tell You Something?

A bad Intake Air Temperature (IAT) sensor can cause problems that seem serious but are often simple to fix. Because this sensor helps control the air-to-fuel mixture, a bad reading can make your truck's engine run poorly. If your 1994-1999 GMC C1500 is showing symptoms like bad fuel economy or a rough idle, this small sensor could be the cause.

Don't Ignore the Check Engine Light

The most common sign of a bad IAT sensor is the Check Engine Light. Ignoring it can lead to worse fuel mileage, failed emissions tests, and in some cases, long-term engine damage from running too rich or too lean.

Choosing the Right Aftermarket Sensor

For a straightforward part like the IAT sensor on a 1994-1999 C1500, you don't necessarily need to pay dealer prices for an OEM (Original Equipment Manufacturer) part. Quality aftermarket brands provide reliable performance at a better price. The technology is simple and has been around for a long time.

  • Standard Ignition (Standard Motor Products): This is a well-known brand in the aftermarket world. They are known for making quality parts that are tested to perform like the original. Many professional mechanics trust Standard parts for everyday repairs.
  • True Tech: This brand is often positioned as a value choice. While there is less specific information available for their sensors, reviews for service centers using "True Tech" parts are generally positive, indicating a focus on honest, reliable service. For a simple sensor on an older truck, this can be a cost-effective option.

Pro Tip: For this specific part and vehicle, a reputable aftermarket sensor is a smart choice. The cost savings are significant, and the part's function is not complex, making it a low-risk replacement.

How Much Does a New IAT Sensor Cost?

The cost to replace the IAT sensor is low, especially if you do it yourself. The part itself is affordable, and shop labor should be minimal due to how easy the job is.

Part TypeEstimated Cost
New Aftermarket$19.54 - $30.24
New OEM (ACDelco)$28 - $40
Shop Labor$50 - $100

Frequently Asked Questions

Where is the IAT sensor located on a 1994-1999 GMC C1500?

On these trucks, the IAT sensor is typically located in the air intake tube, between the air filter box and the throttle body. It's usually a small plastic sensor with a two-wire connector, pushed into a rubber grommet in the intake duct.

Can I replace this sensor myself?

Yes, this is one of the easiest repairs you can do. It requires no special tools. You simply unplug the electrical connector, pull the old sensor out, push the new one in, and reconnect the plug. The entire job usually takes less than 15 minutes.

Are there any recalls for this part?

No, there are no specific recalls on the Engine Intake Manifold Temperature Sensor for the 1994-1999 GMC C1500. Searches of the NHTSA database did not show any recalls related to this component.

What's the difference between an IAT and a MAT sensor?

IAT stands for Intake Air Temperature, while MAT stands for Manifold Air Temperature. They do the same job. On older vehicles, the sensor was often threaded directly into the intake manifold (MAT), while on newer ones it's more commonly found in the air intake duct before the throttle body (IAT). For these trucks, the terms are often used interchangeably.

Technical Specifications

OEM Part Numbers: 25168491 213-4663

Typically a two-wire thermistor sensor that plugs into the air intake duct. Resistance changes with temperature to send a voltage signal to the engine's computer.

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 Engine Intake Manifold Temperature Sensor for:
  • GMC C1500: 199419951996199719981999
In this article
🛍️ Shop This Part
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