GMC Sierra Overheating While Idle: Causes + Fix

There are a few reasons why your GMC Sierra would be overheating when idling.  The most common ones include a bad thermostat, water pump, electric fans, and low coolant level.  This guide is intended to help you find the cause of this overheating in the most efficient way possible.  So, let’s start with what’s easy … Read more

GMC Sierra:  P0068 MAP/MAF Throttle Position Correlation

P0068 in the GMC Sierra is a generic OBD II code.  In layman’s terms, it means that the MAP (manifold absolute pressure) and/or MAF (mass airflow sensor) are providing the Sierra’s computer contradicting data compared to what it should be in relation to the throttle position sensor. The throttle position sensor tells the computer how … Read more

GMC Sierra: Engine Smoking Causes + Diagnosis

A smoking engine is a serious thing.  If your GMC Sierra’s engine has smoke coming from it, it needs to be addressed right away.  It can be caused by quite a few different problems, none of which should be ignored. The most common reasons why your Sierra’s engine would smoke include overheating, burning oil, or … Read more

GMC Sierra Hesitating to Start (5 Most Common Reasons)

While it may not leave you stranded, a vehicle that hesitates to start can be very concerning. There are a few reasons why your GMC Sierra may not be starting, such as a bad starter, a bad battery, bad alternator, and more.   GMC Sierra Hesitates to Start: Causes Here are some of the most … Read more

GMC Sierra:  Bad Sway Bar Links (Common Symptoms)

Sway bar links are responsible for connecting your GMC Sierra’s sway bar to the chassis.  The job of a sway bar is to eliminate body roll by helping the tires keep better contact with the road, which improves the handling characteristics of your Sierra.  If you have a bad sway bar link, your vehicle will … Read more

GMC Sierra Shuts Down While Driving (Common Causes)

If your GMC Sierra is shutting down while driving, it’s a real safety hazard.  Vehicles are a lot harder to control without power brakes or steering. Below is a list of the most common reasons your Sierra would randomly die while driving.  Before looking at anything, is the check engine light on?  If it is, … Read more

GMC Sierra:  Brake Lights Not Working Diagnosis

Brake lights are one of the most critical safety features that your GMC Sierra has.  They let other drivers know when you are slowing down, and that they need to slow down too.  If your brake lights aren’t working, you’re way more likely to get rear ended than normal.  The good news is that troubleshooting … Read more

GMC Sierra: What’s Causing That Rotten Egg Smell?

One of the most undervalued diagnostic tools is the human nose.  There’s a lot our nose can tell us about a vehicle with a few quick sniffs.  If you happen to smell a rotten egg smell coming from your GMC Sierra, it is certainly a cause for concern.  It is most commonly associated with a … Read more

GMC Sierra Dies After Starting Diagnosis

It can be very disconcerting if your GMC Sierra is starting and then dies.  It is most likely caused by some type of issue with the electrical or fuel system.  But, there can be other causes as well. Your Sierra’s engine needs 3 things constantly and in the proper proportion to keep running. Air Fuel … Read more

GMC Sierra: Brake Lights Stuck On → Diagnosis

It is both frustrating and unsafe to drive your GMC Sierra if the brake lights are stuck on.  The most common reason that they stay on is a brake light switch that has failed.   How Brake Lights Work Brake lights work by having an electric current sent to the brake pedal switch at all … Read more