Diagnose Learn AI Scanner

Learn/Misfires & rough idle

AI4Car / Diagnostics

Misfires & rough idle

Patterns behind shaking, misfires and uneven running.

Other topics

← Topic overview All stories Diagnostics Warning lights Misfires & rough idle Starting & stalling Codes & scan data Emissions & exhaust

Search this topicSort stories

#P0300 ⌄

Find a hashtag

All hashtags #misfire17 #ignition9 #roughaftersparkplugs6 #misfirecountonecylinder5 #coldstart4 #P03004 #roughidle4 #battery1 #checkengine1 #coolingsystem1 #fueltrim1 #idle1 #injector1 #overheating1 #oxygensensor1 #P03011 #P03021 #safety1 #scantool1 #vacuumleak1 #vibration1

4 storiesClear filters

A MINI's random misfire returned after a reset

The owner of a 2008 MINI Cooper S reported a random misfire at idle after an earlier ECU reset seemed to help temporarily.

#misfire #P0300 #roughidle

P0300 only on the first cold start

One driver reported rough running and a P0300 warning on the first start of the day.

#battery #coldstart #misfire

P0300 on four Silverado cylinders

A 2000 Silverado showed a flashing check-engine light and P0300.

#misfire #P0300 #scantool

P0300 means the misfire pattern is not limited to one cylinder

Random or multiple-cylinder misfire codes call for a system-level check before chasing individual parts.

#P0300 #misfire #ignition

Page 1 of 1End of topic

AI4Car · Learn, diagnose, understand

Understand the warning. Know what to check next.

Explore fault codes, practical guides, and tools for your own car.

Clear car guides, fault-code help, and tools for your own vehicle.

support@ai4car.com

Explore

Diagnose
Learn
AI Scanner

App

Download
How it works
Pricing

AI4Car

About
Contact
Privacy
Terms

© 2026 AI4Car. Except content under identified licenses.Built for people who want to understand their cars.

Misfires & rough idle — AI4Car Learn | AI4Car