Nissan Driveability Case Study and More Covered in Free New Wells ‘Counterpoint’ Newsletter
The technical services team at Wells Vehicle Electronics offers a detailed diagnostic case study covering Nissan variable valve timing (N-VCT) and an in-depth look at crankshaft position sensors in the latest issue of Wells’ popular CounterPoint newsletter.
Diagostic Dilemmas: Lost in ‘The Diagnostic Woods’
This real-world case study of a 2002 Chevy S-10 pickup, a 1995 Buick and a 1995 Lincoln Town Car illustrates why “chasing” trouble codes can get you lost in the Diagnostic Woods.
Tech Tip: Cam and Crank Sensor Diagnosis
Today’s cars have several different methods of producing spark and setting fuel injector pulses. All of the sensors create a nominal voltage by way of what is referred to as a “Hall effect,” either from an external magnet mounted on the cam gear or body of the distributor housing, or it has its own small magnet inside itself and the Hall effect is created by passing the sensor over or near a piece of slotted metal.
Crankshaft and Camshaft Position Sensor Diagnosis
Nothing is more frustrating than diagnosing an intermittent cranking, no-start complaint with no diagnostic trouble codes (DTCs) and no apparent failure pattern. Much of the time, the cranking, no-start complaint lies with a failing crankshaft or camshaft position sensor. Many of these failures can be heat-related and might require several warm-up cycles to duplicate.
Tech Feature: General Motor’s Ecotec 2.0L Turbo Engine
General Motors introduced its powerful Ecotec 2.0L direct
Tech Feature: Sports Compacts – Performing in a ‘Maturing’ Market
What started out in the 1990s as an affordable way for kids to bang around with cars that were often handed down from their parents or siblings, later grew into a fledgling market all its own.
Tech Feature: Diagnosing Automotive Lab Scope Dilemmas
Although digital storage oscilloscopes or “lab scopes” have now become standard equipment for most modern automotive repair shops, they still possess a mystique that tends to intimidate many technicians. Right off the top, a lab scope is basically a voltmeter that displays voltage signals along a time base. The vertical scale measures the amplitude or amount of the voltage and the horizontal scale measures an incremental time line along which the signals are displayed.
Tech Tip: Sheared Crankshaft Sprocket Keys Found on Some GM 6.2L Diesel Engines
A new, hardened washer, p/n 23504011, is available for improved clamp load of the crankshaft sprocket to the crankshaft by the crankshaft bolt. Installation torques for the hardened washer have been increased to 177 to 185 ft.lbs. (240 Nm /250 Nm).
Tech Tip: Oil Leak by Crankshaft Seal on Porsche Boxter Engines
Engine oil leaks in area of crankshaft sealing ring on flywheel side may be coming from the crankcase and intermediate-shaft flange bolts.
Tech Tips: FLASH Reprogramming – GM Crankshaft Variation Relearn Procedure
A Crankshaft Variation Relearn Procedure must be performed if on 1996 and newer GM vehicles if: the ECC was reprogrammed; the crankshaft position sensor has been replaced; or the ECC has been replaced.
Tech Tip: Ford Truck No-Start Following CKP Replacement
After replacing the Crankshaft Position Sensor (CKP) and/or connector to correct another problem, the engine turns over, but does not start. The fuel injectors pulse a couple of times when the engine starts cranking, then they stop pulsing. There is an rpm reading on the scan data for a split second, then it goes to zero. There is no spark.
Tech Feature: Detecting Misfires in OBD II Engines
With OBD II, there’s no missing misfires. Most engine control systems with OBD II monitor the speed of the crankshaft between cylinder firings to detect misfires. The powertrain control module (PCM) notes the relative position of the crankshaft via the crankshaft position sensor (CKP) each time a trigger pulse is sent to the ignition system.