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.
2004 Ford Taurus 3.0L V6 P0174 and P0191: Check Engine Light On, Loss of Throttle Response at Highway to City Speed Changes
I have a 2004 Ford Taurus with a 3.0L V6 engine. Recently, the check engine light came on, and I noticed a severe loss of throttle response—especially when transitioning from hi...
2004 FORD TAURUS | P0174P0171 OBD2 Code on 1997 Mazda 626 2.0L: How to Fix Lean Mix & Pass Emission Test
Hi, I've had the check engine light on for two months, and my OBD2 scanner consistently shows fault code P0171 — indicating a 'System Too Lean' condition. My vehicle is a 1997 ...
mazda 626 | P0171P0303 Jeep Cherokee
P303 code came up on the obd machine 2001 has 42,000 miles what could the problem be
Jeep Cherokee | P0303P0455 Dodge Dakota P0442
I have checked the vacuum lines running from the control unit to the tank and do not find any cracks etc. I have used a vacuum pump to check the system, small line to the contr...
Dodge Dakota | P0442P0795 and P0708 OBD2 Codes on 2001 Saturn SL2: Transmission Range Sensor Fault Diagnosis and Fix
My 2001 Saturn SL2 experienced erratic overdrive shifting shortly before a full transmission replacement was performed about six weeks ago. After the new transmission was instal...
2001 Saturn SL2 | P0708P0327 Knock Sensor Fault Diagnosis and Fix for 2001 Chevrolet Silverado 5.3L V8
I own a 2001 Chevrolet Silverado LS extended cab with a 5.3L V8 engine and automatic transmission, currently at approximately 140,000 miles. After driving about 5,000 miles post...
2001 Silverado 5.3L | P0327P1359 Diagnostic for 1997 Honda Prelude - Check Engine Light On
The vehicle appears to be running normally with no noticeable performance issues, but the check engine light is illuminated. The fault code P1359 has been detected, indicating a...
PRELUDE | P1359P0401, P1359, P0420 Fault Codes on 1997 Honda Prelude - How to Fix and Reset
My 1997 Honda Prelude has triggered three check engine light codes: P0401 (EGR Flow Insufficient), P1359 (Manufacturer-Specific DTC), and P0420 (Catalyst Efficiency Below Thresh...
PRULUDE 97 | P0401P1401 Diagnostic and Fix for 2001 Ford Mustang 3.8L V6 - EGR Pressure Sensor Issue
I own a 2001 Ford Mustang with a 3.8-liter V6 engine. I purchased it used with the check engine light on. The vehicle originally had a broken flange on the passenger-side exhaus...
2001 Mustang | P14012002 Toyota Camry P0303 Code: Cylinder 3 Misfire - Diagnosis & Solutions
I own a 2002 Toyota Camry (4-cylinder, 40,000 miles, manual transmission) that consistently displays the P0303 diagnostic trouble code, indicating a misfire in cylinder #3. I ha...
Camry | P0303P0354 Ignition Coil Fault in 1998 Ford Expedition 5.4L V8 with 4WD and 94K Miles
I'm experiencing a P0354 diagnostic trouble code on cylinder #4 of my 1998 Ford Expedition with a 5.4L V8 engine, automatic transmission, and 4WD. The issue is located in the re...
98 Expedition | P03541996 Chrysler Town & Country P0171 Fuel Efficiency Issue - High Fuel Consumption
Hi everyone, I'm Frank from Puerto Rico. I own a 1996 Chrysler Town & Country with a recurring OBD2 fault code P0171. After clearing the code, it returns quickly and the vehicle...
96 Chrysler | P01711996 GMC Safari AWD Won't Start with P0102 Mass Air Flow Circuit Low - Diagnosis and Solutions
I own a 1996 GMC Safari AWD van equipped with a 4.3L engine. It was running normally until the 'Service Engine Soon' light illuminated, after which the engine suddenly died as i...
96 GMC Safari AWD | P010202 Vette Catalyst Monitor Not Ready: Causes and Fixes for Emissions Testing
What is the catalyst monitor, and what causes it to remain 'not ready' during emissions testing? The catalyst monitor is a function within the Powertrain Control Module (PCM) t...
02 vette | P2177P0125 OBD-II Code on 2001 Ford F150: Causes, Diagnosis & Resolution
Even experienced users like the site administrator occasionally encounter OBD-II trouble codes. Last weekend, while driving my 2001 Ford F150 (with 58,000 miles) on a highway fo...
2001 Ford F150 | P01251997 Crown Victoria Emission Test Failure: Resolving P0136, P0161, P0401, P0402, P0304 Fault Codes
I own a 1997 Ford Crown Victoria and have failed two consecutive emission tests in Illinois. I've already replaced the EGR valve, two O2 sensors, spark plugs, and ignition wires...
Unknown | P01361999 Chevrolet Tahoe P1345 Code: What It Means and How to Fix It
I own a 1999 Chevrolet Tahoe, and the SES (Service Engine Soon) light has come on. My friend used his Palm Pilot with an OBD-II decoding program, which detected fault code P1345...
99 Tahoe | P13451999 Mercury Cougar P0171 P0174 P0401 and P1405: Causes and Repair Guidance
I brought my 1999 Mercury Cougar (V6) to a friend's shop, where their scanner detected the following OBD2 fault codes: - P0171: System too Lean (Bank 1) - P0174: System too Lea...
99 Mercury Cougar | P01712001 Ford Windstar P0171 and P0176: Intake Manifold Gasket Failure & Lean Codes After Repair
I leased a 2001 Ford Windstar for two years before purchasing it, which gives it a solid maintenance history. The check engine light first appeared in late 2004. I drove the veh...
2001 Windstar | P0171Practical 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.