B251C Porsche 928 Diagnostic Trouble Code

B251C Porsche 928 code definition:
B251C is a kind of OBD-II Diagnostic B-Body Diagnostic Trouble Code for Porsche 928.

B251C Porsche 928 is defined as Ignition Coil B Primary/Secondary Circuit Malfunction.This code is a generic trouble code, meaning it applies to all vehicles equipped with OBD-II tool, or vehicles made since 1996 up to present. As you drive and when specific conditions are slowly met, the vapors will gradually purge from the charcoal canister and will get burned within your engine.

Symptoms

Symptoms of a B251C Porsche 928 diagnostic trouble code may include:

Misfire
Misfire
The light may stay on or light intermittently as the DPF regenerates. The engine will be sluggish on acceleration.
Reduction in engine performance, especially at low RPM levels

Possible Causes :

An air leak forward of the DPF will change the sensor readings resulting in the code
Rusty exhaust systems, cracked exhaust manifolds or damaged or missing gaskets or donuts will cause air leaks.
Fuel with a large percentage of sulfur will clog the DPF quickly

Common Misdiagnoses

IC Circuit High Voltage Problem
Control Module Throttle Actuator Position Performance Problem
Air Conditioning (A/C) Clutch Feedback Circuit High Voltage Problem
Cruise Vehicle Speed/Set Speed Difference Too High Problem
PCM Stack Overrun Problem

Repair Processes :

Now, clear the codes and test-drive the vehicle to see if the code is reset. If the engine displays a miss and there wasn't a code, determine which cylinder is misfiring. If the exhaust manifold is visible, spay or pour a small amount of water on each cylinder exhaust port. Water will evaporate immediately on good cylinders and slowly on the missing cylinder. If this can't be accomplished pull the plugs and check the condition. Find out what kind of system you have and verify that voltage to the fuel level sensor is present at the fuel pump wiring harness.

Process Tips

Diagnostic trouble code B251C Porsche 928 is not difficult to diagnose and repair. Thus, it always pays to have a qualified technician to look after your vehicle should this error code arise.

Diagnosing this code requires the engine to be in good running shape, without unmetered air entering the engine. If other codes that relates to misfiring condition, lean running or air entering the engine is present, then you must first fix those error codes before B251C Porsche 928.

Fortunately, B251C Porsche 928 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.