Underhood Service: Troubleshooting Troublesome Injectors
Clean fuel injectors are a must for peak engine performance, fuel economy and emissions. If the injectors are dirty and can’t deliver their normal dose of fuel, then performance, fuel economy and emissions are all going to suffer. Dirty injectors can’t flow as much fuel as clean ones, nor can they deliver the correct spray
Carburetor Repairs & Recalibrations
As a follow-up to “Dusting Off Fuel System Fossils” in April’s edition of Underhood Service, I will share many driveability concerns and emissions failures that I’ve repaired by rebuilding, and sometimes modifying, certain carb circuits. But before diving into a carburetor rebuild or recalibration, be certain that you understand the system you’re working on, including
Confronting the Complete Cooling System Service
By now, it’s obvious to most service shops that cooling system service is an absolute “must-do” on any nameplate. Once a cooling system suffers long-term neglect, it turns into an ongoing source of problems for the owner and his service technician because, when corrosion starts to take place, the effects can’t be reversed. For that
How Engine Oil Becomes Engine Sludge
Fresh engine oil is a clear, free-flowing liquid blend of base stock and additives that contains no fuel, water, coolant, dirt or other contaminants. In engines that have failed prematurely, the oil has very often been transformed into a high viscosity deposit of brown or black goo, commonly referred to as “sludge.” When regular engine
Diagnostic Dilemmas: Driving Forces Behind a Driveability Technician
He used to be known as the tune-up guy, the shop troubleshooter or the ace mechanic. Today, he’s known as a driveability tech. Tomorrow, when body control electronics come on full line, he’ll probably be known as an electronics diagnostics technician. Whatever his name might be, most of us know that driveability techs are smart,
Editor’s Notebook
With the month of June comes graduation ceremonies and commencement speeches that are filled with emotion and congratulatory remarks, words of encouragement, and challenges to graduates to fulfill their dreams, make their mark on society and change the world to make it a better place. These “dreams foster goals, and achievement brings success” messages should
Mercedes-Benz Engine Diagnostics
I’ve always loved the puzzle. Check Engine warning lights have become an everyday chore for me over the last five years. It’s a challenge that extends my interest and creativity in the auto service profession. Before I deal with some specific Mercedes-Benz faults that I’ve researched, I must say that the ability to really solve
Muscling in on Restoration Work: Part 2
There’s a hot trend in the automotive aftermarket to return car owners to the past. Literally. Today, aging baby boomers are spending big money on “recapturing the rapture” of the cars of their youth. Just turn on your television any evening and you’re sure to find some type of automotive program on the cable and
OBD II Diagnostics:Tips And Tricks to Make the Process Easier
The Malfunction Indicator Lamp (MIL) can be a golden light of opportunity for your shop. If the light comes on, it means the Onboard Diagnostics II system (OBD II) has detected an emissions-related problem. OBD II is designed to turn on the MIL if a problem occurs that may cause emissions to exceed federal limits
Muscling in on Restoration & Performance Work: Part 1
As automotive technology continues to become more complex with each new model year, you may be longing for the “good ol’ days” when engines had carburetors and distributors but no sensors, fuel injectors or computers. Most driveability problems were fairly simple to diagnose and only required a trained ear and a few basic tools. Alas,