Why is my 1994 4runner randomly misfiring
I bought a 4runner a month ago and ever since ive had it its been randomly misfiring. Cold or hot it still misfires every so often. Under a load like a steep hill it misfires like crazy. What could be the problem?
Check the plug wires. If the wires are old, they may be arching instead of firing the spark plug. Take a peek under the hood at night (or in a dark garage) to see if you can see or hear any arcing.
I looked at all the cables and didn't see anything wear or cracks. When it was running I didn't hear or see any sparking.
Next thing to check would be the cap & rotor and also pull the spark plugs and check for buildup, wear, and gap.
How would I check the cap and rotor? Just look to see if anything is different? I'm 17 and trying to learn more about mechanics. I did take one spark plug out and it looked good. Should I check them all? Pretty hard to get to
A misfire normally means the spark is not getting to the spark plug. You are looking for carbon build up on the contacts. Here is a YouTube video: https://www.youtube.com/watch?v=OoZcDY3kCdg
Here is another video of how to diagnose an intermittent misfire: https://www.youtube.com/watch?v=jXWWPjRr3oY
when I was 17 there was no internet , I'd go to the library to read the chilton manual , education is free , certification costs money ,
Those videos helped a lot. So I took the cap and rotor off and they looked good. The rotor did look a little dirty. It wasn't shiny. So should I start with changing the cap and rotor?
The rotor does look a little burnt
yes , any pitted , discolored electrical contacts should be replaced
