Fix It

The air temperature sensor on the 1997 Chevrolet Tahoe monitors the temperature of the air flowing through the intake into the filter. The engine computer regulates the fuel to air ratio based on the temperature readings from the sensor. Buy a new sensor from an auto parts retailer, and change it at home. The sensor mounts in an accessible location and requires no disassembly to access it.

Instructions

1

Raise the hood of the Tahoe. Support it with the prop rod.

2

Locate the air cleaner assembly at the top of the engine compartment, near the firewall. The air cleaner assembly is a large black box with air intake hoses attached to either side and clips securing the cover.

3

Look for a small wire running to the passenger side of the air cleaner assembly, just above the intake hose. The air temperature sensor connects to the end of the wire, threaded into the air cleaner assembly.

The air filter in the 2003 Ford Focus PZEV 2.3L is different from a standard filter. A standard filter is a small paper cartridge that is placed inside an air filter assembly. The Focus PZEV -- which stands for "partial zero emissions vehicle" -- uses an air filter box with a special nonserviceable foam element inside. In order to replace this filter, you have to replace the entire box, which is fairly expensive. But you should only have to replace the filter every 150,000 miles.

Instructions

1

Lift the hood of the Focus and prop it open.

2

Locate the air filter box. It is the large black box just behind the left headlight.

3

Unbolt the air filter box from the air intake hose using the socket wrench and socket.

4

Remove the air filter box from the engine bay and place the new one in its place.

5

Connect the new air filter box to the air intake hose and bolt it into place.

A sure sign of air conditioning problems is a lack of cool air coming out of the vents in your van or other vehicle. The problem might be with the compressor or motor, but it might just be a leak. The leak might not be your only issue, but it must be addressed before fixing any other components of the air conditioning system.

Instructions

1

Look in your vehicles owners manual to determine what type of rigerant your van uses.

2

Set the rigerant leak-detector to the appropriate setting. The setting varies based on the type of rigerant your vehicle uses. It is typically labeled CFC, HCFC or HFC, and must be set correctly to locate the source of the leaks.

3

Move the rigerant leak-detectors sensor along the air conditioning hoses and other components, looking for the indicators of a leak. The indicators vary in different rigerant leak-detectors, but are often represented by a buzzer or other sound.

4

Pay special attention to connection points. Move the sensor across all sides of the hoses and other components.

5

Mark each leak with masking tape. This allows the mechanic addressing the leaks to easily locate it.

The National Automotive Parts Association, more commonly known as NAPA, sells its own line of automotive tools under the brand name Evercraft. The Evercraft brand includes a line of pneumatic (air-powered) tools. These tools are sold at certain NAPA stores across the country as well as through the companys website.

Evercraft Impact Wrench

Evercraft impact wrenches use pneumatic power to twist on heavy lugs on wheel rims and other parts. The 3/8-inch Butterfly impact wrench has an aluminum housing and operates at a speed of 10,000 revolutions per minute (RPM). It has a maximum torque of 75 foot-pounds. It is a little over 6 inches long, weighs 2 lbs. and uses a 3/8-inch air hose. The 1/2-inch impact wrench is even more powerful with a maximum torque of 230 foot-pounds.

Evercraft Air Ratchet

Producing 45 foot-pounds of torque with 170 RPM at 90 pounds per square inch (psi), the Evercraft Air Ratchet has a ribbed handle to allow the user better control. It also has an aluminum and steel housing. It is 8.9 inches long and weighs 2.8 lbs.. It uses a 3/8-inch hose and has an average air consumption of 4 cubic feet per minute (CFM).

Evercraft Air Hammer

An air-powered hammer that produces 3300 strikes per minute at 90 psi, the Evercraft Air Hammer has a built-in regulator for added control with an air consumption of 5.1 CFM. It has a bore diameter of 11/16th inch, a stroke length of 2.6 inches, a total length of 6.9 inches and a weight of 3.5 lbs.

Evercraft Die Grinder

A high-impact, pneumatic tool used to grind down materials such as metal car parts, the Evercraft die grinder has a safety throttle lever, a rear exhaust mechanism and a built-in regulator. It also has a ball bearing construction that adds to the durability of the tool. It spins at 22,000 RPM and is 6.75 inches long. The company also makes a 90-degree angled die grinder with similar specifications.

Evercraft Utility Cutoff Tool

The Evercraft utility cutoff tool is a device used to cut metal car parts. The utility cutoff tool has a metal guard, a built-in regulator, a safety throttle lever, ball bearing construction and a rear exhaust mechanism for blowing debris away from the worker. It has a free speed of 20,000 RPM and 7.125 inches long.

Hot air is not as dense as cold air and therefore requires less fuel to balance an engines air/fuel ratio. The intake air temperature sensor keeps track of the temperature of the air going into an engine. This vital info is then used by an engines computer (PCM), which allows it to keep air/fuel mixture in balance.

Process

An intake air temperature sensor is normally positioned in the intake manifold so that its tip can meet the air going into the engine. The PCM sends around 5 volts to the sensor and waits for a voltage signal response. Air intake sensors have certain resistance reactions to different air temperatures, and this resistance will determine the voltage reading thats sent back to the PCM.

Problems

Faulty air intake temperature sensors can provide incorrect readings to a vehicles PCM. This can cause the PCM to mistake warm air for cold air, which will result in incorrect air/fuel mixture. This in turn leads to idling problems, which can cause a car to shut off, especially in cold weather. Other driving problems include trouble accelerating as well as engine surging.

Reasons

There are several reasons why an air intake temperature sensor can fail, such as bad electrical connections, which lead to incorrect sensor output. Oil from the intake manifold can also coat and contaminate the sensor, limiting its ability to properly monitor air temperature.

Air conditioning (AC) compressors are a must for proper cooling and can appear in applications such as vehicles or homes. An auto AC compressor is considered to be the most vital of all the parts in a vehicles air conditioning system and is often referred to as the heart of the system. Having information on an AC compressors functions can be beneficial to homeowners and auto owners.

Residential Vs. Auto

AC compressors can vary in location depending on if its for an auto or residential application. An auto AC compressor is connected to a vehicles engine. A residential AC compressors is usually located outside the home encased within a sealed unit.

Auto Compressor Functions

An auto AC compressor has two sides which are vital to how it functions. A suction side allows gases produced from refrigerant to be pulled in. The compressor then compresses the gases and uses its discharge side to transfer them for use to other parts of the system.

Residential Compressor Functions

A residential AC compressor is a pump which brings in refrigerant gas as well. In a residential compressor, this refrigerant gas is brought in through a large suction line. The compressor then uses compression to change the refrigerant into a highly pressurized gas which is then sent to be used in other parts of the system.