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.
P0174 O2 Sensor Issue and Poor Fuel Economy on 2001 Nissan Frontier SE 6CL
I have already replaced the MAF sensor, but my fuel efficiency remains around 12 miles per gallon and the check engine light is still illuminated. The light occasionally turns o...
6CL 01 Frontier SE | P0174P0456 OBD2 Code on 2002 Dodge Dakota: Evaporative Emission System Leak Diagnosis and Solutions
I recently encountered a recurring P0456 diagnostic trouble code on my 2002 Dodge Dakota with a 4.7L engine. The code indicates a small evaporative emission system leak. I repla...
Dodge Dakota | P0456P0420 on a low mile LS1
Im having a P0420 fault code come up. I clear it and it comes back within 2 weeks. Its a totally stock 2000 Trans Am WS6 with 62k on the odometer. I cant believe the cats ar...
LS1 | P0420P0171 & P0174 Diagnosis for 1999 Ford Explorer V6 - Oxygen Sensors, MAF, and Vacuum Leak Solutions
I own a 1999 Ford Explorer 4x4 with a 148,000-mile V6 OHV engine. The vehicle has been well-maintained: oil changes every 3,000 miles using synthetic oil, a K&N air filter insta...
Ford Explorer | P0171Honda civic P0141. I have tried everything to my knowledge
I have a 99 honda civic dx. I put a after market exhuast on it with a test pipe (off road pipe). I had my mechanic splice the wire to my 2nd O2 sensor to it will be long enough...
Honda Civic | P0141P0455 and P0442 on 2001 Dodge Ram 4x4 Quad
Sounds great Jeff. I don't know how you would fax it to me. But I don't know everything either! I guess it couldn't be e-mailed either? Let me know here, which way I could ...
2001 Dodge Ram 4x4 Quad | P04422000 Ford Focus P0171 Code: PCV Valve Fix & Recalled Fuel Pump Connection?
My 2000 Ford Focus SE Sedan with a 2.0L SPI engine and 97,000 miles recently triggered a P0171 code after a fuel pump replacement under recall service. I've already replaced the...
ford focus | P0171P0741 Diagnostic Guide for 1999 Chevrolet Venture - Torque Converter Clutch Issue
I'm encountering a P0741 diagnostic code on my 1999 Chevrolet Venture, and I'm wondering if anyone can provide guidance. The code appeared during a routine check, and it's not r...
99 Chev Venture | P0741How to Fix P0420 Fault on 1999 Mazda626: Complete Solution Guide
I recently encountered a P0420 diagnostic code on my 1999 Mazda626. After replacing the air filter, spark plugs, PCV valve, and manifold oxygen sensor, I still experience sympto...
Mazda626 | P0420P0123 TPS Fault Diagnosis and Repair for 2000 Dodge Durango (125K Miles)
Hello everyone, I own a 2000 Dodge Durango with 125,000 miles. It has been in excellent condition overall and runs smoothly when towing my 31-foot boat. However, I've recently ...
TPS | P0123Nissan Sentra 2001 GXE P0171 Code: Causes, Fixes & Recall Information
I recently encountered Error Code P0171 on my 2001 Nissan Sentra GXE after driving approximately 70 km following a fuel refill and the addition of a fuel injector cleaner. The c...
Nissan Sentra | P01711996 Olds Silhouette Van P0401 Code: EGR Issues and O2 Sensor Behavior Explained
I own a 1996 Oldsmobile Silhouette Van with a persistent P0401 code. I've already replaced both the MAP sensor and the EGR valve, but the check engine light returns within just ...
OLDS SILHOUETTE VAN | P0401Dakota 0442 Code: How to Locate and Fix Vacuum Leak (With Gas Cap & Hose Tips)
I'm experiencing a recurring check engine light with code P0442 on my Dakota. The issue returns every 2-5 days, typically after a cold start and about one mile of driving. I've ...
Dakota | P0442P1406 OBD2 Error Code Explanation and Fix for 1996 GMC 350 4x4 with Auto Transmission
I own a 1996 GMC 350 4x4 with automatic transmission, stock setup. My vehicle is currently displaying a P1406 OBD2 diagnostic error code. I'd like to understand what this code m...
GMC Truck | P14062001 Ford Taurus P1401 Code: How to Diagnose and Fix EGR System Fault
My 2001 Ford Taurus has a trouble code P1401. This code indicates an issue with the Exhaust Gas Recirculation (EGR) system, specifically either a valve position sensor providing...
Ford | P1401PO420 Fault in 2001 Pontiac Grand Prix: Catalyst System Efficiency Below Threshold - What Does It Mean and How to Fix?
I own a 2001 Pontiac Grand Prix SE and my Check Engine Light has come back on after being temporarily fixed. The diagnostic tool shows code PO420 — Catalyst System Efficiency Be...
2001 PONTIAC GRAND PRIX | P0420P1300 Diagnostic Issue on 1995 Ford Ranger with 2.4L Engine
I'm experiencing a P1300 diagnostic error on my 1995 Ford Ranger equipped with a 2.4-liter engine. The only related issue I've found is a suspected boost failure. However, I'm u...
95 Ford Ranger | P1300Practical 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.