2014 Editions Archives - Page 2 of 4 - UnderhoodService
A/C Oil Service: Avoid Compressor Failure With Proper Maintenance

HVAC systems often fail because the air conditioning compressor fails. Not following the proper service procedures or compressor oil recommendations could be factors that contribute to premature compressor failure. Refrigerant Since the mid-‘90s, all vehicles have been using R-134a refrigerant, but soon, vehicles will arrive at your shop equipped with R-1234yf refrigerant. This is the

AC Oil Compressor failure
How Engine Coolant Temperature Sensors Influence The Modern Powertrain

  Considering that roughly 1,500 or more ­different vehicle models are introduced into our domestic market each year, it’s becoming more difficult to predict how a powertrain control module (PCM) will utilize data from a particular sensor or detect an out-of-range sensor in any single vehicle platform. The engine coolant temperature (ECT) ­sensor provides a

ECT sensor data diagnostics
The Best Tests For Fuel Delivery Systems

The ancient Greek philosopher Heraclitus said that there is nothing permanent except change. Greek history aside, it’s easy to spot change in our current market because vehicle fuel delivery technology has evolved to ­include conventional, pulse-modulated and direct fuel injection fuel delivery systems, with each having a specific set of components and testing issues. In

Testing Fuel Delivery Systems
Everything You Need To Know About Stretch Belts

Stretching the belt may seem counter intuitive after everything you have been told about serpentine belts. But stretching the belt with the right tools is often the only way stretch belts can be installed. Stretch belts can take loads off of the main accessory belt drive, allow for better packaging and solve NVH problems that

2014 4.3L V-6 EcoTec3 AFM VVT DI (LV3) for Chevrolet Silverado and GMC Sierra
Variable Displacement: The Future of the Oil Pump is Here

Almost every major OEM has an engine or engine family that uses a variable displacement oil pump that is controlled by the ECM to deliver the best possible pressure and efficiency. When it comes to improving fuel efficiency, 3% to 5% are huge numbers. Achieving those fuel efficiency numbers while also increasing the power to

Variable Displacement Oil Pumps
Most Common Causes of Misfire Codes

A flashing check engine light and a P0301 to P0312 diagnostic trouble code (DTC) is a surefire indication that one or more cylinders are misfiring. Occasional misfires may pass unnoticed, but a steady misfire is hard to miss. The engine usually feels rough, lacks power and uses more gas than usual. Sometimes a misfire may

Spark Plug Worn Rings
Pattern Failures of MAF and MAP Sensors

Pattern failures are those failures that happen over and over again — and the same applies to how customers describe these failures. Customers might unknowingly give you the answer to their problem without needing to open the hood. In this article, we will look both at the failures of these sensors and the actual customer

MAP Sensor
Toyota Hybrid Oil Change

Does the thought of changing the oil on a Toyota Prius scare you? Are you afraid you could be shocked with more than 200 volts? Don’t be afraid, changing the oil is not radically different than any other Toyota. Changing the engine oil on just about every hybrid doesn’t require disconnecting the hybrid drive system,

Toyota Prius Oil Change
10 Signs A Fuel Injector Needs To Be Replaced

In the past 30 years, the fuel injector has moved from the intake manifold to the combustion chamber. During this evolution, injectors have become more precise in dispensing fuel. If this precision is thrown off by restrictions, electrical problems or fuel problems, it can cause driveability issues. These are the top 10 signs fuel injectors need service or replacement.

Do’s and Don’ts of Carrier Gaskets

Don’t  Add sealants to carrier gaskets. Most carrier gaskets are designed to be installed dry. They do not need extra help to create a seal. Silicone can get in the ridges and change the bead geometry and the gasket’s ability to seal. Do Replace a plastic intake manifold if there are any signs of cracking

10 Tips For Serpentine Belt System Inspection And Service

1. Where is the wear? Like a tire, the friction between the belt and pulleys wears away at the belt, usually on the tops and walls of the ribs. Eventually the grooves of the pulleys will bottom out on the grooves of the belt, and then the belt will start to slip. According to one

HVAC Sensors: More Than Just Temperature

When a driver sets a temperature in the control head of an HVAC system, what does it mean to the vehicle? Seventy-two degrees could mean many different settings depending on the outside temperature, humidity and even the position of the sun. When a passenger decides that 70 degrees is a better temperature for their zone,

HVAC air circulation