March 2018 Archives - UnderhoodService
GM Power Steering Pump Replacement Tips

An analysis of returned power steering (PS) pumps that had been replaced for noise, no power assist, no or low pressure and leaking conditions has indicated a high number of “No ¬≠Trouble Found” results. When attempting to repair a power steering concern, the steering system ¬≠analyzer should be used to assist the technician in a successful diagnosis.

Demystifying Scopes: Engine Camshaft And Crankshaft Waveforms

Having to remove valve or front cover of an engine to check engine timing marks can rarely be completed in under an hour on most modern engines. But, capturing the waveforms from the camshaft and crankshaft sensors can be completed in under 30 minutes. This diagnostic approach can also diagnose circuit and sensor problems.

ACEA Oil Specifications: New ‘Sequences’ Mean Better Oil Performance Characteristics

ACEA standards are based on testing developed by the European Engine Lubricants Quality Management System (EELQMS). Think of ACEA as the SAE of Europe and EELQMS as the API/ILSAC in the U.S.

OBD II Emissions Monitors

OBD II is primarily emissions-driven and will set codes anytime a vehicle has a fault that may cause emissions to exceed federal limits by 1.5 times. It doesn’t necessarily mean the vehicle has a real emissions problem. Many times it does not. But, if the nature of the failure is such that it might cause emissions to rise, OBD II will set a code anyway. That is why some states are allowing motorists to opt for a second-chance tailpipe test if their vehicle fails an OBD II test. In many instances, the vehicle will pass the tailpipe test.

Shifty Battery Drain

Typically, when you’re doing a parasitic draw test, you watch the meter and wait for the amperage load to drop and the various systems to go to sleep. But on this truck, something was staying awake. Time for a different approach to the problem.

Honda: iVTEC And Timing Chains

In this article, we’ll be taking a look at a 2003 four-cylinder Accord that came in with a check engine light complaint, but no reports of driveability issues. It was due for a New York state inspection, so it had to be repaired. The code was persistent, setting itself consistently on the second startup.

Spark Plug Fouling Diagnostics

Spark plugs are the “canary in the coal mine” of the combustion chamber. The electrodes and porcelain can show short- and long-term problems if you know what to look for.

MLS Gasket Update

The days of getting away with composition gaskets in extreme combustion situations were back when the deck surfaces on blocks and heads were thick and strong, and the heads were clamped with 5-6 head bolts per cylinder. However, all that changed when car makers became extremely weight conscious for MPG reasons and they started removing material out of blocks and heads.