Quote:
Originally Posted by markweatherill
You remove one spark plug, lay it on the engine or hold it there (carefully)somehow so it has good ground connection, start the engine and run it, long enough to see what the spark is like. I'm sure there are videos on Youtube that explain it better. 
Alternatively, there's a device called a Gunson Colortune, I had one years ago. |
I tested the spark this way, but never let the car actually run more than a second.
It shudders and kicks, and sounds awful, so I always shut it down if it does happen to start on just 3cyls.
Surely running the car on 3cyl is bad for the car !