Code p0302, cylinder misfire?

1997 MERCURY MOUNTAINEER

156,000 MILES • 5.0L • V8 • 4WD • AUTOMATIC

MOUNTAINMAN97

MEMBER
1 POST

Chugs in overdrive idles rough, throws code p0302. When I check cylinder 2 plugs look good, light brown tinge color, put new plugs and wires all cylinder still same problem, plug never looks fouled on any cylinder. Don't think it's the injector because plugs look good. No codes other than p0302.

Mar 7, 2023 at 5:27 PM

STRAILER

✓Experienced Mechanic
55,604 POSTS

It still can be the spark plug just to let you know. I would do a full tune up including coils, wires and plugs. Here is a guide to help you step by step and I have included how to change the ignition coils out as well in the images below.

Replacement Spark Plugs (Either side) .................... AWSF32EE

https://www.2carpros.com/articles/how-to-tune-up-a-car-engine

Make sure you change ethe plugs wires one at a time. Check out the images (below). Please let us know what happens.

Images (Click to enlarge)