These EVAP monitors can be run in two different ways. Ford, GM and some Asian imports use a vacuum to run the monitor. Chrysler, most European and a few Asian products use pressure to run the monitors.
Ambient temperature affects tire pressure, and in the new world of TPMS, where the vehicle is constantly vigilant of tire pressure, these sometimes subtle changes in pressure could trigger the TPMS. For each 10° F of ambient temperature, tire pressures will change about 2%, or about 1 psi.
Oil specifications are not about the ingredients in the oil, but how the oil reacts to standardized conditions.
Stretch belts can take loads off of the main accessory belt drive, allow for better packaging, and solve NVH problems that can occur with a longer serpentine belt. Less belt means less tension and fewer noise and vibration problems.
The ECM’s (engine control computer) function is to control emissions, monitor and regulate engine functions as well as optimize engine performance and fuel consumption.
Relationships are what make this industry what it is today. For decades, the parts industry was virtually unchanged in how the repair shop and the parts supplier relationship functioned. That is, until the late ’80s when computers became an integral part of many repair shops, making parts ordering simpler with less interaction between the parts store employee and the repairer.
Code numbers and definitions are a strategic direction for the repair. These tools allow a trained mechanic to know which pathway to take. The real “machine” that finds out what is wrong with a car is the brain of the very guy or gal working in the bay.
Being able to use a scope allows you to make a more accurate diagnosis faster. It is a tool that can prevent that second call to a customer advising them the initial estimate did not work. It can also be a triage tool that can save you from having to remove plugs to perform a compression test or give additional evidence if a misfire is electrical or mechanical.
I love technology and completely understand the value of this technology and the vital investment in scan tools, scopes and telematics, but I also value watching a trained maestro wave his wrench and use his God-given ears to lean in to diagnose a problem.