Editor, Underhood Service Magazine
Differentials And Diagnostics

A differential allows the two connected wheels to spin at different rates.

Power Window Regulator and Motor Service

Power windows are great as long as they roll up and down when commanded to do so.

Replacement Alternator Pulley Problems

Replace the OAD and tensioner with the belt as part of a mileage-based service. Sponsored by Litens.

Inspection Tips For Chain-Driven Water Pumps

If one water pump fails sooner and is replaced without an investigation, the new pump is likely doomed.

Water pump feature
Throttle-By-Wire Diagnostics

Throttle-by-wire systems proactively manage the air and fuel going into the combustion chamber.

Hyundai & Kia Hybrid Drivetrain

The Hyundai hybrid system has a motor control unit (MCU) and hybrid control unit (HCU).

Acura Turbo Engine Service

It is important to check the operation of the solenoids that control vacuum to the actuators.

Why Do Timing Chains Stretch?

As the timing chain wears, it can change the timing of the camshaft and crankshaft.

Subaru EJ25 Head Gasket Problems

Most of the EJ head gasket failures occur around the 100,000-mile mark and start as a slow oil or coolant leak.

Different Nameplates, Different Expectations

One thing Asian nameplates share is that the system voltage must stay in a specific range during the reflashing procedure.

Determining Catalytic Converter Efficiency

Almost every part on the engine determines how long a catalytic converter will last.

New Oil Specifications

Many 0W16 oils have a new donut certification mark on the bottle called API SN-PLUS and SN-PLUS Resource Conserving.