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Tech Tip 0198

Diagnosing Engine Misfires: Would You Have Considered Engine Coolant or Oil Leaks?

Tech Tip #198

When diagnosing a misfire condition most automatically assume an ignition or fuel related condition as the culprit. This would involve a defective spark plug, ignition wire, ignition coil, fuel injector, etc. While these components are the most likely candidates that would result in a misfire, some other conditions must also be considered with today's engines when making the diagnosis.

Tech Tip 0197

Making An Accurate Diagnosis: Always Start with the Basic Checks First

Tech Tip #197

New technology poses new challenges. Many of these challenges require more than the information provided in repair manuals or diagnostic code charts. Much is learned once the vehicle is put into service and into real-world vehicle operating conditions. Following are some conditions that can promote difficult to diagnose symptoms...

Tech Tip 0196

Fuel Facts: Troubleshooting Rough Idle, Surging, Stalling, Hard Starts and Noises

Tech Tip #196

Determining if the performance symptom is due to the vapor pressure of the fuel, carbon buildup, or sticking valves due to gum and varnish can be a challenge.

Tech Tip 0103

Charging System Problems: There's More to "Em Than Just a Dead Battery

Tech Tip #103

The next time you tackle that impossible-to-diagnose performance problem, you may want to consider a charging system related problem. And then the high or low voltage condition may be an ECM-PCM or a scan tool just leading you astray. Consider the following situations that eluded some sharp technicians..

Tech Tip 0195

Brake Solutions: Service Tips for the Brake Technician

Tech Tip #195

The owner of the 2013 Ford F150 encountered a brake performance issue, which involved a pulling condition during brake application. The vehicle was a recent purchase with little maintenance history from the previous owner, other than an invoice in the glove compartment that reflected a recent disc pad replacement...

Tech Tip 0194

Vehicle Modifications: They Can Create Diagnostic Challenges

Tech Tip #194

Vehicle modifications can create some interesting challenges for a technician. The first step in the diagnostic process is a discussion with the vehicle owner, and if possible, have them accompany you on a road test. Always perform the basic diagnostic steps first. Determine if any modifications have been made to the vehicle. With today’s technology and vehicle design, it is not uncommon to introduce a problem with the addition of an accessory or device. Let’s consider some examples that can lead to some difficult and elusive symptoms.

Tech Tip 0193

GM’S Active Fuel Management: Camshaft and Valve Lifter Failures

Tech Tip #193

GM’s Active Fuel Management (AFM) system allows a V8 engine to turn off half of its cylinders for fuel economy purposes. In doing so the V8 engines RPO: L76, L77, L83, L86, L94, L99, LC9, LFA, LH6, LMG, LS4, LT1, LT4, LY5 and LV3 are developing a history of camshafts and valve lifters being turned into scrap metal. The symptoms of a cam or lifter failure usually involve a chirping, ticking, squealing or squeaking sound accompanied by a Check Engine light and engine misfire codes stored in memory. The misfire condition may not be evident to the vehicle operator... 

Tech Tip 0192

Changes in Engine Lubrication: Prompts Changes in Filtration Technology

Tech Tip #192

Today’s automotive engines have different filtration and lubrication requirements compared to engines produced in the past. Bearing clearances and the composition of the metal used in the bearings, plus changes in engine technology require different lubrication and filtration characteristics. Some assume that any viscosity oil will do and filtration efficiency s determined by the physical characteristics/dimensions of the filter alone. Filters of equal size often share different efficiency...

Tech Tip 0191

Electrical Challenges: A Battery of Facts Mush Be Considered

Tech Tip #191

Most vehicle owners think of the battery as a component that starts the engine and serves no other purpose. And most never think about the battery or consider having it tested until the engine fails to start. With today’s vehicles, the battery may start the engine perfectly right up until it fails to start without any warning to let the vehicle owner know they have a problem...

Tech Tip 0190

Chevrolet Colorado and GMC Canyon: The Challenge of an Oil Filter Replacement

Tech Tip #190

Changing the oil filter on a 2017-2018 Chevrolet Colorado or GMC Canyon with a 3.6L engine can be a challenging event, often leading to engine failure. These are not applications to hurriedly perform a lube service on. If extreme caution is not taken the customer may be without transportation for a few days until a new oil filter housing can be secured...

Tech Tip 0189

A Diagnostic Challenge: The Symptoms May Be a Normal Characteristic

Tech Tip #189

Often we are faced with customer complaints that are seemingly impossible to resolve. We methodically make our best diagnostic efforts and implement the necessary repairs to alleviate the customer’s complaint. Sometimes, our best efforts fail to provide a solution and when this happens, it looks bad on the technician and the parts supplier.

Tech Tip 0188

Carbon and Gum Deposits: Their Effect on Engine Performance

Tech Tip #188

Two vehicles with no-start symptoms…both due to fuel related issues.

On one vehicle the customer complaint started with a misfire condition which progressed to an extended crank time to start and eventually a no-start symptom. Performing the basic checks revealed...

Tech Tip 0187

Scheduled Maintenance: Can Prevent Costly Engine Repairs

Tech Tip #187

Timely vehicle maintenance makes good business sense, especially when compared to costly engine repairs or an engine replacement. The extended service intervals have created a major concern for the old school generation, and especially technicians that have serviced vehicles for thirty-plus years. Our early driving and maintenance experience encompassed less fuel...

Tech Tip 0186

Controlling Oil Pressure: It's a Matter of Regulation

Tech Tip #186

When examining oil filters that are deformed from excessive pressure, filter gaskets blown or canister lock-seams unrolled, there is a reason for these conditions. While the oil filter is usually blamed for these conditions, the actual cause is over-pressurization due to a malfunction within the oil pump. Read on for pressurization issues involving GM, Kia and Hyundai...

Tech Tip 0185

Low Oil Pressure Message: Locating the Mystery Filter

Tech Tip #185

A low oil pressure message/light is becoming a common complaint on 2007-2016 GM vehicles equipped with a V8 engine and active fuel management (AFM), which is sometimes referred to as displacement on demand (DOD). These symptoms often occur with no indication of a low oil pressure condition such as engine related noises...

Tech Tip 0184

Neglected Services: The Results Can Be Costly

Tech Tip #184

The primary objective of thorough inspections and system maintenance is to prevent some unnecessary and costly repair expense for the customer. System neglect can result in hundreds of dollars in repair cost that may have been circumvented by performing some basic maintenance...

Tech Tip 0183

Battery Management: The Challenges of a Smart System

Tech Tip #183

Do you know all there is to know concerning a battery replacement? Most assume they do, but later they may realize they should have done some research. Technology changes the way we must perform some services and troubleshoot some systems. Based on the application, battery replacement is becoming a technical procedure that may require a skill level above the average do-it-yourselfer with some basic tools. Instead, the service may require some specialty tools.. 

Tech Tip 0182

Brakes and Suspension Solutions: For Some Difficult to Diagnose Symptoms

Tech Tip #182

Front Brake Caliper Leak

GM has identified a defect in certain 2015 Chevrolet Colorado and GMC Canyon vehicles whereby the front brake calipers on these vehicles can leak brake fluid. The condition is caused by tiny air pockets in the caliper castings that occurred during the casting process. If the casting contains a continuous string of air pockets that penetrate the casting, brake fluid leakage can occur. This condition can result...

Tech Tip 0181

Oil Filter By-Pass Valves: Some Are Hidden in Plain Sight

Tech Tip #181

It is imperative that the lube tech fully understands the importance and function of the oil filter bypass valve. The by-pass valve provides protection for the engine by ensuring adequate lubrication in the event of a filter restriction or during periods of high oil pressure or pressure surges, such as that encountered during cold weather starts/snap throttle...

Tech Tip 0180

Chrysler's 3.6L Pentastar Engine with Oil Filter Housing Leakage

Tech Tip #180

Imagine changing the oil and filter on a customer's vehicle and a few days later they return with a repair bill totaling several hundred dollars for a new oil filter housing to correct an oil leakage problem...