We are going to do something a little different this time in the Fine Tuning department. We ran into a diagnostic case study you might be interested in. It involved a 2001 Chevrolet Impala with about 40,000 miles on it. The A/C fan and cruise control would intermittently stop working while the customer was driving. There seemed to be no rhyme or reason to the failure. The vehicle could be driven for days before the problem would occur.

We continue our investigation of engine knock sensors with a look at one and two-wire sensors. In the previous issue of Counter Point, we discussed the various causes of engine knock. Prior to the age of electronic engine control, an engine designer had a limited number of effective tools to guard against engine knock. Principle among these were combustion chamber design, the octane of the fuel used and mapping of the spark advance curve. The designer couldn’t risk the possibility of engine damage caused by knock, so it was always necessary to keep the engine well short of the point where it might begin. This assured engine longevity, but hurt performance.

Part 2: Analyzing Amperage Results When Testing Ignition Coils with a Low Amp ProbeCheck out Part 2 of Barry Gersten's Current Ramping series. This time, he covers how to analyze amperage results when testing ignition coils with a low amp probe.

Show Me Tools brings you the Laser Toe Gauge... Check out the popular Toe In Tool with .004″ accuracy from Advantage Wheel Alignment. This tool is for Professional Heavy Duty Toe Gauge Designed for Auto Repair Shops or Truck Repair Shops, even on UN-Level Surfaces!

Are you getting the most out of your scan tool? Automotive Video Inc. This is a 2-part class that teaches technicians how to take full advantage of the latest features of their Solus, Modis, and Verus scanners. Scot Manna, AC Delco’s Technician of the Millennium who also runs a beta test shop for Snap-On Tools, is the expert trainer in these programs.