Diagnostics Archives - UnderhoodService
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.

Mode $06 Misfire Diagnosis

Understanding why ‘Mode $06’ was developed and how it works to identify misfires.

Solving Intermittent Overheating

New cooling systems anticipate and influence changes in coolant temperature.

ADAS Calibration Tips

Here are 10 tips to follow during ADAS Calibration.

Repairing Wiring Harnesses

A guide to probing and poking.

Ignition Systems

The ignition coil is a very simple and robust circuit.

Auxiliary Cooling Pumps

An auxiliary cooling pumps primary function is to circulate warm coolant to the heater core.

Alternator Testing For No Charge Conditions

Many alternator problems turn out to be nothing more than a bad connection at the alternator or a bad wiring harness.