Question

What needs to be done if the engine light is on in the 1995 Nissan Altima 2400? I have the engine code P0420

Answer 1

start by checking

1. Intake air leaks

2 Spark plugs may be faulty

3 Fuel injector leak or bad

4. Three way catalyst converter Bank 1
- Exhaust tube
last- Improper ignition timing
last- Engine Control Module (ECM)