Q1: My car shows codes like P0420 / P0171 / P0138. What do they mean?
These are common codes related to the fuel system or oxygen sensors:
P0420: Catalyst efficiency below threshold
P0171: System too lean
P0138: O2 sensor voltage high
They often indicate a worn oxygen sensor, exhaust leak, or ignition issue. If you're not sure, simply tell us your year, make, model, and engine—we'll check the exact part you need.
Q2: My engine shakes at idle. Is my ignition coil bad?
It's very possible. Common symptoms of a failing ignition coil include:
Rough idle or shaking
Hard cold starts
Poor acceleration
Higher fuel consumption
Misfire popping noise
Tell us your vehicle info—our team can help you identify the cause.
Q3: What are the symptoms of a bad oxygen sensor?
Typical signs include: Check Engine Light on, Increased fuel consumption, Poor acceleration, Strong fuel smell, and Slow throttle response.
Most sensors should be replaced every 80,000–100,000 km.
🔍 2. Fitment & Compatibility
Q4: How do I know which oxygen sensor fits my car?
Just provide: Year, Make, Model, and Engine size.
We'll confirm: Upstream or downstream, Correct connector, Proper OEM reference number, and Federal vs. California emissions compatibility.
Q5: What's the difference between OEM and aftermarket ignition coils?
OEM: Same quality as the factory part; long-lasting.
High-quality aftermarket: Close to OEM but more affordable.
We only offer high-grade, reliable ignition coils.
Q6: How many oxygen sensors does my car have?
Most vehicles have 2–4 sensors (Upstream front and Downstream rear). We can confirm the exact number for your vehicle.
🛒 3. Buying, Quality & Concerns
Q7: Are cheap oxygen sensors reliable?
They work for a short time but usually cause issues like short lifespan, slow response, and frequent check engine lights.
We only sell new, high-quality, fully tested sensors.
Q8: How can I avoid buying a refurbished or used auto part?
Check for scratches on the connector, dirty wiring, or marks on threads.
Our parts are 100% brand new, never refurbished, and fully tested.
🧰 4. Installation & Usage
Q9: Can I install an oxygen sensor myself?
Yes. Difficulty: medium.
You'll need an O2 sensor socket, Anti-seize compound, and a Torque wrench. We recommend clearing fault codes with an OBD scanner after installation.
Q10: Do ignition coils need programming after replacement?
In most vehicles, no programming is required. Just swap the old coil with the new one.
💰 5. Value & Performance
Q11: Your parts cost less than OEM. Are they really reliable?
Yes—our parts use the same-grade materials and testing standards as OEM suppliers. Because we don't go through dealer channels, the price is much more affordable.
About us
Automotive Leader started with a simple mission: to provide mechanics and DIYers with OEM-grade parts at affordable prices.
China Address
Room 602, No. 152 Helong East Road, Helong Subdistrict, Baiyun District, Guangzhou City Postal Code: 510000
U.S. Address: 7600 LTC Parkway 34986 PORT SAINT LUCIE, FL - United States
Phone Number: +86 15812449181
Email: support@automotive-leaderstore.com
Logistics Policy
1. U.S. Warehouse (Standard Option) Handling time: 1-3 business days Transit time (days): 3-6 business days via USPS/UPS/FedEx.
2. China Warehouse (Standard Option) Handling time: 1-3 business days Transit time (days): 14-22 business days via USPS/UPS/FedEx.
Refund and Return Policy
30-Day Return Policy / Return shipping is free.
We do not accept direct exchanges.
After receiving and inspecting your returned item, we will notify you whether your refund has been approved.
If approved, the refund will be processed back to your original payment method within 5 business days.
Please note that your bank or credit card company may also require additional time to process and reflect the refund.
If you have not received your refund within 10 business days after your return request has been approved, please contact us.