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.
1998 Chevrolet Lumina P0303 Fault Code: Diagnosis and Repair Guidance
I've performed an ignition test and compression test on cylinder #3 (cylinder 185), and have replaced the spark plugs. Currently, cylinder #3 appears wet, which is indicating a ...
1998 Lumina | P030301 Eclipse GT P0421 - Warm-Up Catalyst Efficiency Below Threshold (Bank 1) Diagnosis and Repair Guidance
I'm experiencing fault code P0421 on my 2001 Eclipse GT, which indicates 'Warm-up Catalyst Efficiency Below Threshold (Bank 1)' as reported by my PocketScan Plus. The code has b...
01 eclipse GT | P04212007 Mazda5 Multiple OBD2 Codes P2196, P2-187, P0455, P0131 - How to Diagnose and Fix Without Dealership Costs
My 2007 Mazda5 has been acting up recently — it won't start unless I fully depress the accelerator pedal while cranking. Once it starts, it runs roughly for a few seconds before...
2007 Mazda5 | P013197 chevy blazer p0300 solid then blinks
hey all. First I want to introduce myself as Josh, and let you all know that all my driving is done on highways, not city because this neck of the woods is all highway. I have ...
97 chevrolet blazer | P03001999 Ford Ranger P0303 Cylinder 3 Misfire: Diagnosis and Solutions
I own a 1999 Ford Ranger with a detected cylinder 3 misfire (OBD2 code P0303). I recently completed a tune-up, and took the vehicle to an auto parts store to have the coil packs...
1999 ford ranger | P0303P0139 OBD2 Code Recurring in 2002 Hyundai Elantra GLS (Auto, 99K Miles)
I recently encountered the P0139 diagnostic trouble code on my 2002 Hyundai Elantra GLS with automatic transmission and 99,000 miles. The code is commonly associated with a rear...
2002 Hyundai Elantra GLS | P01392003 Kia Sedona P0141 Code: Front Bank O2 Sensor Failure After Exhaust Replacement
I'm having serious trouble passing my annual emissions test, and I've already failed it twice. Despite spending over $450 on repairs, the vehicle still fails. Here's what I've ...
2003 Kia Sedona | P01412004 Ford F150 P2195 Code After Installing Gibson Stainless Headers
I recently installed Gibson Stainless headers on my 2004 Ford F150 4x4 and now the check engine light is coming on. My Edge Color Screen Programmer displays a diagnostic code of...
2004 F150 | P2195P0455 OBD2 Code Explanation and Troubleshooting for 1997 Jeep Grand Cherokee
I own a 1997 Jeep Grand Cherokee, and the check engine light has activated. The diagnostic trouble code P0455 indicates a large evaporative emission system leak, possibly origin...
1997 Jeep Grand Cherokee | P04552001 Chevrolet Suburban P0300 Code: Misfire on Cylinders 5 and 6 - Diagnosis & Solutions
I own a 2001 Chevrolet Suburban with a 5.3L engine that is showing a P0300 fault code indicating a random misfire, specifically affecting cylinders 5 and 6. I've already perform...
2001 chevrolet suburban | P03001999 Ford Explorer XLT P1151 and P0171: How to Diagnose Vacuum Leak or Fuel System Issues
My 1999 Ford Explorer XLT with a 4.0L engine has had the Check Engine light on for some time. After investigating, we found fault codes P1151 and P0171. We've tried checking for...
1999 Ford Explorer XLT | P01712001 Nissan Maxima P0300 Misfire - Help Needed with Diagnosis and Fixes
We've been troubleshooting this issue for over a week, and the only fault code we're getting is P0300. The vehicle runs roughly most of the time and struggles to climb hills—bar...
01 maxima | P0300Honda Civic VTi Engine Fault Codes P1399 and P0325 - Loss of Acceleration and Stalling
I recently replaced the engine in my Honda Civic VTi, but now the vehicle experiences a significant loss of acceleration and stalls unexpectedly. The engine runs smoothly at idl...
honda civic v tec | P03252001 Nissan Maxima SE P0270 Fault: Is It Just a Speed Sensor Issue or Could There Be Deeper Problems?
I recently purchased a 2001 Nissan Maxima SE and am currently experiencing the OBD2 diagnostic code P0270 — 'Output speed sensor circuit malfunction'. My main concern is whether...
01 Maxima SE | P02702007 Toyota Camry 3.5L V6 with P0606 Code: Second ECU Replacement Not Resolving Issue
Hello everyone! I'm experiencing a persistent issue with my 2007 Toyota Camry (engine 3.5L, automatic transmission, federal emission standards). The car starts normally but aft...
Camry 07 | P0606P0008 Fault in 2007 Holden VE Commodore LY7: Why Engine Light Only Appears After Restart?
Hi everyone, I'm experiencing a recurring issue with my 2007 Holden VE Commodore LY7 and would appreciate some insight into what might be causing the P0008 code (Engine Positio...
Holden VE Commodore LY7 | P0008OBD-II P0401 Code Explanation for 1996 Ford 302 Bronco - Exhaust EGR Flow Insufficient
I'm looking for clarification on what the OBD-II P0401 code means on my 1996 Ford 302 Bronco. My code-key reader displays 'exhaust' as the related system. Can anyone explain the...
1996 Ford 302 Bronco | P0401Practical 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.