Diagnostics Archives - Page 6 of 46 - UnderhoodService
GM Stop/Start Vehicles

It is essential to understand what is different on these vehicles and how it might change your diagnostic approach.

Cooling System Leak Testing

What replaces the conventional water pump and thermostat is electronic thermostats and electric water pumps.

DTC P0171 And The Connection to Carbon Deposits (VIDEO)

Carbon deposits could be causing code P0171. This video is sponsored by Rislone.

Getting Rid Of Code P0420 With A Little Cleaning (VIDEO)

A good cleaning might be all you need to get rid of code P0420. This video is sponsored by Rislone.

BMW Spark Plug Replacement

Here are a few things that you need to know before replacing spark plugs in a BMW.

Oxygen Sensors And Catalyst Efficiency

Newer air/fuel ratio or wide-band sensors can detect a wide range of fuel conditions.

ZEUS Diagnostic Tool Now With Flag Tracker Feature

With flag drop function, simplified navigation and updated graph view, this feature simplifies the diagnostic process.

Fuel Pressure Diagnostic Service

Use a scan tool that can look at special direct fuel injection parameters and perform bidirectional tests.

Knock Sensor Diagnostics

The knock sensor is not the only sensor responsible for detecting engine knock.

Best Practices for Turbo Services (VIDEO)

Turbo performance can only be impaired by mechanical damage or debris. Sponsored by Standard Motor Products.

The July Digital Edition Is Now Available To Download, Read

ShopOwner includes technical and management content and is free to download and read.

Misfire Codes After A Spark Plug Replacement (Video)

After replacing spark plugs, you may get a handful of misfire codes. This video is sponsored by Autolite.