Tech Tip: Audi MIL Is On, Misfire DTCs P0300-P0312 Set
If an Audi customer complains that the engine has reduced performance without a significant loss of power or stalling, verify if Campaign 28F2/J1 has been performed (model years 2002-’07 only). Also determine if the vehicle is experiencing rough idle, the MIL is flashing or constantly illuminated, or one or more of the following DTCs are stored: DTC P0300 (Random/Multiple Cylinder Misfire Detected); DTC P0301-P0312 (Cyl. 1-12 Misfire Detected).
Mercedes-Benz: Managing Misfires, Solving Those Strange, Intermittent Engine Vibrations
Automotive Electronics Diagnostician Sergio Fernandez discusses how to solve those strange, intermittent engine vibrations on a 2003 E320, with 3.2L V6 engine and 120,000 miles. The diagnosis begins with these findings: DTC P0305, misfire on cylinder #5; and DTC P0301, misfire on cylinder #1.
Misfire Testing with a Scan Tool
In this tip clip, instructor Jim Wilson talks about P0300 codes and misfire testing using your scan tool. He talks about how you would look at certain things such as RPM, MAP, changes in load, and long term fuel trims. He goes on to mention some things technicians should be aware of on Ford and Chrysler vehicles.
This clip is an excerpt from the 90 minute comprehensive “Functional Scanner Testing” training program with Jim Wilson, available from Automotive Video.
Tech Tip: Dodge/Jeep Engine Misfire at Idle
This bulletin applies to vehicles equipped with a 3.7L engine in which the customer may experience occasional engine misfire at idle. The malfunction indicator lamp may illuminate for single or multiple cylinder misfire.
New Airtex Vehicle Electronics Video Unlocks Secret to Intermittent Misfires on Dodge Caravan
The technical services team at Airtex Vehicle Electronics was recently presented with a confounding diagnostic challenge on a 2001 Dodge Caravan, and the troubleshooting process and ultimate solution have been captured in a fascinating new diagnostic video available on YouTube.
Diagnostic Solutions: Diagnosing Misfires
Although diagnosing misfires can be a tough assignment for any driveability technician, the diagnosis can be made much simpler if he understands the basics of misfire diagnosis. For example, when the first OBD II misfire monitor was first introduced in 1996, technicians were puzzled by problems with false misfire diagnostic trouble codes (DTCs). Case in point, vehicles being driven on washboard dirt roads began recording false misfires.
Tech Feature: Courage Under Misfire
Generally, when a customer brings a vehicle into a shop that has a misfire concern, they will describe it as bucking, jerking or loss of power. They also may describe it, depending on the cause, as a jerking when they take off from a start, but smoothes out once the vehicle gets moving. They may tell you the check engine light has been flashing.
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.
Engine Maintenance: OBD II Diagnostics, Misfire Codes, Fuel Trim Faults, Driveability and More
As automotive electronics diagnostics continues to evolve, so do the tools that are need to diagnose and repair today’s complex engine and electronics systems. This lineup will arm you will some diagnostic tips and give you some invaluable service advantages on Porsche, BMW, Hyundai and Mazda models.
Toyota Tech Tip: MIL On, Misfire DTCs Set on 1MZ-FE Engines
Some vehicles equipped with 1MZ-FE (V6) engines without VVTi may exhibit a rough idle and/or an MIL-on condition with a diagnostic trouble code or codes for misfire caused by an improperly operating ignition coil assembly. Production changes have been implemented to prevent this condition from occurring.