May 2023 Archives - UnderhoodService
Ignition Coil Output

To see inductance inside the primary windings, use an amp probe placed around the positive wire for the ignition coil.

HV/EV Battery Pack Replacements

It is difficult to say when a battery pack will need to be replaced.

Compressor Oil for R1234yf

Working on R-1234yf systems is not that different from the R-134a variety.

Artificially Generated Customer Service

As easy as it is to TALK about customer service, actually offering it is NOT automatic. 

Engine Bay Covers: Cosmetic or Comedic?

Each year, it seems engine bay covers get bigger and more difficult to remove.

GM Diagnostic Tip on Misfires, Noises and DTCs

Determine which description best matches the vehicle you are working on, and perform the suggestions as necessary.

Fuel Pumps and Cranking

Diagnosing the problem comes down to understanding what causes a loss of fuel pressure.

Read The May Magazine Online Now

Each issue includes technical content from Underhood Service and other ShopOwner channels.