Traditional gasoline car fault
Search fault code and browse forum case posts.
This page is designed for quick diagnosis on gasoline vehicles by combining code lookup with real discussion cases. Enter a fault code to filter related topics, then compare symptom context such as cold start behavior, acceleration load, fuel-trim deviation, ignition misfire pattern, and recent maintenance history. Many codes can be triggered by shared root causes, so use cross-checks from multiple posts before replacing sensors, coils, injectors, or catalytic components.
2000 Honda Civic P0420 Code After Aftermarket Distributor/Coil Replacement - Solutions & Diagnostics
I own a 2000 Honda Civic that recently triggered a P042-0 diagnostic trouble code (DTC) after replacing the distributor and coil assembly. The vehicle experienced a sudden loss ...
2000 Honda Civic | P0420P0340 Fault in 2005 Ford Taurus SE (Vulcan 3.0 V6) - Can It Be Driven Safely?
2005 Ford Taurus SE with a 3.0L Vulcan V6 engine and automatic transmission, currently at 149,000 miles. The Check Engine Light (CEL) has been on steadily for the past few days,...
2005 Ford Taurus (Vulcan 3.0 v6) | P0340P0404, P0490, P0190 & P0251 Fault Codes on 2003 Ford Mondeo 2.0 TDCI - Diagnosis and Solutions
Hi there, I own a 2003 Ford Mondeo (Europe) with a 2.0L TDci engine (115 PS), model codes HJBA or HJBB, having covered approximately 278,000 km. Recently, I've noticed inconsis...
ford mondeo 2.0 tdci | P01902002 Ford Focus ZTS P1237 Diagnostic: Engine Light On, Stalling After Fuel Pump and Filter Replacement
I recently replaced the fuel pump and fuel filter because my 2002 Ford Focus ZTS would not start. After the replacement, the car starts and runs, but the engine light remains on...
2002 Ford Focus ZTS | P1237P0121 Fault Diagnosis and Fix for 2004 Toyota Tacoma 4WD with V6 Engine
I own a 2004 Toyota Tacoma with 4WD and a 3.4-liter V6 engine. Yesterday afternoon, while driving around town, I experienced sudden accelerator malfunction — the gas pedal felt ...
2004 Tacoma | P0121P0404 OBD2 Code on 1998 Chevrolet Blazer: EGR System Failure Diagnosis and Fixes
I recently received a P0404 diagnostic code from my 1998 Chevrolet Blazer, which indicates an 'EGR system failure' — specifically, either an open or short circuit in the EGR pos...
1998 Chevrolet Blazer | P0404P0335 Diagnostic Guide for 1997 Ford Aspire 1.3L with Automatic Transmission
I own a 1997 Ford Aspire 1.3L with an automatic transmission and am currently experiencing the P0335 diagnostic trouble code. I've already replaced the Crankshaft Position (CKP)...
1997 Ford Aspire | P03352005 Ford Focus 1.6tdci Misfire with P0210, P0310, and P138B Codes - Smoke Issue Cures Itself After Driving
Hi everyone, I'm looking for help with my 2005 Ford Focus 1.6tdci. The car is showing multiple misfire-related fault codes: P0210 (Fuel Injector Circuit Malfunction), P0310 (Mis...
Ford Focus | P0210P0138 Fault Code on 2000 Nissan Maxima: Missing O2 Sensor at B2 Position Behind Catalytic Converter
My 2000 Nissan Maxima is equipped with four oxygen (O2) sensors as per the factory specification: B1 and B2 at the front manifold, and B1 and B2 at the rear manifold. However, I...
200 Maxima | P01382000 Chevy 2.2L OHV Engine PO303 Code: No Compression in Cylinder #3, Possible Blown Head Gasket?
My son was driving the 2000 Chevrolet 2.2L OHV engine when he reported a popping sound during downshifting from 5th to 4th gear. The vehicle would stall, spit fuel, and fail to ...
2000 Chevy 2.2 OHV | P03032000 IMPALA P0480 Fault Code: Fan Circuit Issue Diagnosis and Solutions
What is the common cause of the P0480 fault code in a 2000 IMPALA? The vehicle's cooling fan activates when engine temperature exceeds normal levels, but it turns off prematurel...
2000 IMPALA | P04802001 Toyota Corolla P0420 Fault at 125k Miles - Best Catalytic Converter Brands & Fitment Guide
I'm planning to replace the catalytic converter on my 2001 Toyota Corolla with 125,000 miles and am looking for member experiences with popular brands. Specifically, I'm conside...
2001 Corolla | P04202006 Nissan Sentra P0133 Code: How to Diagnose and Fix Air-Fuel Ratio Sensor Issue
2006 Nissan Sentra 1.8L 4-cylinder engine, automatic transmission, approximately 130,000 miles. Two years ago, the vehicle experienced difficulty starting, which was diagnosed ...
2006 Nissan Sentra | P0133P0125 Code on 2003 Toyota Matrix: Is It Really a Thermostat Issue or an O2 Sensor Fault?
I'm experiencing a recurring P0125 diagnostic trouble code (DTC) on my 2003 Toyota Matrix. The engine stays in open loop operation, and the coolant temperature sensor (CTS) read...
2003 Toyota Matrix | P0125P0455 and P0306 Diagnostic Guide for 2002 Jeep Liberty Sport
I'm experiencing two check engine light codes—P0455 and P0306—on my 2002 Jeep Liberty Sport. The vehicle idles roughly, and the check engine light flashes after the engine warms...
2002 Jeep Liberty Sport | P0306P0171 to p0172 2003 trailblazer 4x4 6 cyl
pressure is good BUT that adds to puzzle .. nothing easy the compressor Lt/gn to HVAC module, Dk/Gn to AC relay, if you can see the Blk is ground.. online (GMPARTS>COM) could c...
2003 Trailblazer 4x4 6 cyl | P0171P0154 O2 Sensor No Activity Circuit - 2006 Harley-Davidson Street Bob Diagnosis
I own a 2006 Harley-Davidson Street Bob and am encountering the P0154 diagnostic trouble code, which reads 'O2 Sensor No Activity Circuit'. This error appears during engine diag...
H-D Street Bob | P0154Practical workflow for fault-code troubleshooting
Start by confirming battery voltage and reading freeze-frame data, then inspect wiring and connectors before replacing parts. If the code returns after clearing, record the exact driving or idling condition when it reappears. Prefer case threads with complete repair feedback, because confirmed outcomes provide stronger guidance than one-time symptom descriptions. Following a step-by-step workflow reduces repeated repairs and lowers total diagnosis time.