My 91 4.0 started running rough yesterday. Pulled wire off #6 and no change (idle), replaced plug, no change. What’s the odds my valves are the issue? I’ve got spark to the plug, and fuel.
#6 dead (1 Viewer)
- Thread starter 91landcruiser
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How do you know you have fuel to THAT cylinder?
So funny, I lost a plug wire yesterday! Check cap and resistance of plug wires.
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Run a compression test, or at least get a reading on that cylinder. It won't fire much below 100# of compression.
If it is low, start with adjusting at least those 2 valves. If problem persists, then it's off with his head! (Halloween humor
If it is low, start with adjusting at least those 2 valves. If problem persists, then it's off with his head! (Halloween humor
- Thread starter
- #5
When I pulled plug the second time, it was wet (fuel)
- Thread starter
- #6
Soooo, upon further digging, compression tested, 1-4 cylinders ran 120#, 5&6 had Maybe 20#. Sounded like they were blowing out of each other’s cylinder. That would be a frickin head gasket, huh?
Unfortunately, yes.
nice thing is those 3f heads are much easier to pull than the 1fz. Condolences still.
- Thread starter
- #9
Well, mine looks like a head gasket
glad yours was simple!
I'm sorry. That sucks. You're following me by about a year. I did my head gasket this time last year.
