Techs Helping Techs is turning 12 And it’s time for another roundup of useful tips and tricks courtesy of your fellow technician readers. While our writers share their expertise in every issue, it’s extra special when our readers share what they’ve learned from their days and nights working in the service bay. Thanks to all who shared their advice.

Current ramping is an easy art to learn and returns many good returns. Virtually every 12 volt output device that is controlled by the PCM can be current ramped by using the low inductive current probe non intrusively by simply clamping around the voltage feed wire or the ground side control wire.

Keeping the internal combustion engine as close to the stoichiometric ratio as possible will result in optimum catalytic converter efficiency and fuel economy. The stoichiometric ratio simply means that all the air (14.7 parts) and fuel (1 part) going into the cylinders are being converted to water and carbon dioxide exiting the exhaust. This is the perfect combustion reaction, but this desired stoichiometric operation can’t happen without fuel control.

The process of supplying air to the internal combustion engine’s cylinders is called aspiration, and it involves the induction or intake system of the engine. Engine aspiration takes two forms: naturally aspirated (NA) or forced induction.

What happens when a vehicle’s fuel tank is filled with “bad” fuel? Well, it varies depending on how bad the fuel is and if the engine is gasoline- or diesel-powered. Fixes can range from cleaning the system with a fuel additive (isopropyl alcohol), flushing the system and refilling with “good” fuel, to needing to repair damage to the fuel system and/or engine.

The warning lamps for DSC/ABS and brake warning on a 2012 BMW 528i be illuminated. There may also be a warning in the control display for “Chassis Control System Failure.” 

This bulletin applies to 2017-2018 Audi A4 vehicles equipped with a 2.0 TFSI engine. If the engine is difficult to start or will not start, one of the following codes may be stored: P310B or P0087. 

Some 2014-2020 Toyota 4Runner vehicles may experience the ABS light on with DTC C0226, C0236, C0246 and C0256 stored current in the ABS system. Use a Picoscope to monitor the ground to the skid control ECU with the engine running and headlights on, then with the headlights off. 

This bulletin applies to 2013 Honda Fit vehicles equipped with A/C. If the left dashboard side vent is warmer than the right side vent with the A/C on chances are the evaporator core isn’t being flooded with enough liquid refrigerant, causing it to fully vaporize halfway through the core.

Some owners of 2011-2012 Chrysler Town and Country vehicles may experience an intermittent no-start condition. Upon further investigation the technician may also find DTC B2224 (SKREEM) Sentry Key Remote Entry Module Internal or U0236 (Lost Communication with Column Lock Module) has been set (active or stored).