Got the Lean Cylinder code - how should I approach this?

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Sep 14, 2017
Grand Lake, OK
I have a 96’ LX with 163k that is new to me as of a week ago. No maintenance records. Code P0301 is showing. I cleared it when I got it and have driven about 50 miles and it is now back.

My concern is other people have a cylinder go lean and it isn’t ignition related but rather head gasket troubles.

Should I start replacing ignition sh1t? Or go ahead and get the to a brothel and replace the head gasket?

Here’s no. 1

You electrode should have a slight grayish powder on it. This is normal combustion residue.

Your electrode, from what I can see, looks OK. Also looks like you have the same problem I have, your plug wire seals are shot.

I wouldn't start throwing parts at it, unless you really want a new truck. Don't assume that the problem is related to a cause without evidence. Walk through the fault tree and you'll find the problem.

The fault tree:
FSM wisdom (such as it is)


Just had an issue with lean out on my 94. Turned out to be a tank of bad gas that killed the fuel filter and one injector. I’d check that fuel filter. Just me.
Rodent entry, other than that, no. Duct tape will work in a pinch. It won't look pretty, but that hose is kinda needed.
Okay so I got a multimeter but ran out of light before I could test the injectors. BUT. I took a screen capture of both of my cruisers running. It was about 45 degrees and I assumed the vapor from the exhaust was just that, temperature related. Then I started my tundra and it had zero exhaust, then I started my other cruiser and it had zero vapor or smoke. But the FZJ had a s*** ton of white vapor/smoke emitting from the exhaust. Here is a shot from the video I can’t upload.

Probably condensation. If it is coolant it is an obvious smell.
Hmm. Head gasket?
whats the date code on your plug wires, if their factory wires they will a manufacture date on the wire to give you an idea of how old they are

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