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.
COP Connection: Investigating Common Coil-on Plug Misfires
For a number of reasons, the trend of modern engine management technology is leaning toward using coil-on-plug (COP) ignition systems. One reason is that COP ignitions are very compact and are very adaptable to individual cylinder tuning. With the exception of a few designs that incorporate a driver or “module” into the COP assembly itself,
Tech Tip: Misfires May Cause Engine to Feel Rough, Lack Power and Use More Gas
When you have a misfire code for a particular cylinder, you can focus on one of three things: an ignition problem, a fuel injector problem or a compression problem. Ignition problems that can cause misfires include worn or fouled spark plugs, bad plug wires, moisture on the plugs or plug wires, or a weak or dead ignition coil ….
Tech Tip: Diagnosing Ignition Misfires
A flashing Check Engine light and a P0301 to P0312 diagnostic trouble code is a sure-fire indication that one or more cylinders are misfiring. Occasional misfires may pass unnoticed, but a steady misfire is hard to miss. The engine usually feels rough, lacks power and uses more gas than usual.
Ignition Misfires
A flashing Check Engine light and a P0301 to P0312 diagnostic trouble code is a sure-fire indication that one or more cylinders are misfiring. Occasional misfires may pass unnoticed, but a steady misfire is hard to miss. The engine usually feels rough, lacks power and uses more gas than usual. Sometimes a misfire may feel
Analyzing Ignition Misfires and Plotting a Diagnostic Course
Uh oh. The Malfunction Indicator Lamp (MIL) is on, and you’ve just found a misfire code. It’s a code P0304, which tells you cylinder number four is misfiring. There are no other codes and the engine has a steady miss. Now what? Misfire diagnosis in this kind of situation should be fairly easy. You have
Jaguar V6 Timing Chain Service
When a guide and tensioner fail, it induces timing chain slap that causes the chain to jump on the sprockets.
Audi TFSI/FSI: Oil Consumption And Carbon Buildup
Technical Service Bulletins can be valuable in helping solve vehicle problems. But sometimes, it takes multiple TSBs to find a pattern failure or the “root cause” of a problem. In the case of the Audi/VW 2.0L Fuel Stratified Injection (FSI) engine introduced in 2006, three problems related to engine carbon and fuel issues are connected
Carbon Deposit Q&A
Follow along to learn more about carbon deposits.
Mercedes Ignition Coil Pack Diagnostics
Replacing a single coil might not be the best approach to curing an engine of a chronic misfire.
