underhood service Archives - Page 5 of 86 - TechShop Magazine
Relax – R1234yf Is Not The End Of The World

I attended the Mobile Air Conditioning Society’s 2014 Training Event and Trade Show in New Orleans last month. The main topic of discussion was R1234yf, or “twelve-thirty-four” in A/C lingo. There has been a lot of hype about the changeover to this refrigerant. Don’t panic. The reality is that it is not the “air conditioning apocalypse” some are predicting.

Start Solving Transmission Electronic Control Problems

Troubleshooting an automatic transmission can be one of the most intimidating diagnostic procedures at a shop. The first reaction is typically, “We don’t do that type of work.” But there is profit in performing drivetrain diagnostics and “in-the-car” repairs.

Three Causes Of Transmission Complaints

The modern transmission is one of the most connected components on a vehicle. When using a scan tool to diagnosis a drivetrain problem, it’s often what is not displayed on the scan tool that will lead you to your final diagnosis. Read on for three of the common causes of transmission complaints.

ASE A1 Test Prep: Cylinder Heads and Gaskets

Passing the ASE A1 can be difficult. Do not go into this test with the notion that this is an exam for engine rebuilders. Many of the tasks in the A1 task list are required every day at a general repair shop for top-end engine repairs. Here are some tips.

Platinum prices, catalytic converter thefts on the rise?

Platinum miners in South Africa went on strike toward the end of January. This situation half a world away could have real impact on the price, sales and safety of catalytic converters. Also, read how some resourceful shops are marketing services to guard against the rise in catalytic converter thefts.

Air Filter Fuel Trim Diagnostics

The modern engine measures two things extremely well, the amount of air going into the combustion chamber with the mass airflow sensor (MAF), and the byproducts that are generated by the combustion event with the oxygen sensor. These measurements allow the engine’s computer to put the right amount of fuel and spark into the cylinder to give the most efficient and cleanest combustion event.

Secret Diagnostic Trick: Hint? You Are Doing it Right Now

I was fortunate to have been raised in my father’s auto shop. From the early age of 11, I could be found performing various tasks around the shop from cleaning to observing and helping the technicians whenever an opportunity would arise. I now have my own one-man auto repair facility where I am the only person involved with the repair process of the vehicle. This mandates me making the most efficient use of my time. So, over the next several articles, it is my plan to share with you some of my time-saving diagnostic strategies.

A/C Diagnostics 101: The Value Of Scanners

Leave it to the manufacturers to take a simple thing like heat and air conditioning and turn it into an electronic jungle of wiring, sensors and computer components. HVAC units have come a long way from when I started in the business. Not that I want to dwell on the past, but it might be a good idea to make sure we understand the basics before diving into the problem of today’s systems. I always feel that if I understand a system fully before doing any repair work, I’m more likely to get it right the first time.

Why Oil Balancing Is Critical When Replacing A Compressor

The purpose of oil balancing is to make sure the amount of oil in the A/C system remains at the correct level. The first thing to consider when performing the process is the amount of oil contained in the replacement compressor. This can vary from a full charge of oil (8 oz./236 mL), to a half charge of oil or no oil at all. If oil is contained in the replacement compressor, it will have to be removed and reinstalled in the correct amount to properly balance the system.

GM Tech Tip: Intermittent No Crank/No Start With MIL On And DTCs Set

This repair can be applied to any electrical connection including, but not limited to: lighting, body electrical, in-line connections, powertrain control sensors, etc. Do not over apply lubricant to the point where it prevents the full engagement of sealed connectors. A light coating on the terminal surfaces is sufficient to correct the condition.

VW Tech Tip: No Start/No Crank On Jetta’s Keyless Start System

The customer may state that the engine cranks intermittently or will not crank. This condition may be more evident when the engine is hot. This may be caused internally when the steering column electronic systems control module – J527- fails, causing Terminal 50 to not energize high, which results in a no-crank condition. Models affected: 2005-’07 Jetta (A5) and 2006-’07 Rabbit and GTI (A5).

Why A Clean Fuel Tank Is Important For A Fuel Pump’s Diet

Fuel pump replacement comebacks can be costly and can hurt your reputation. One of the leading causes of failure is the tank. If a vehicle gets 20 miles to the gallon, then more than 5,000 gallons of gas (from many stations) will go through the tank in 100,000 miles. During this time, sediment, rust and debris from the pump can find its way into the tank. Removing all contaminates is critical.