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Discussion Starter · #1 ·
Misses on 2 cylinders. Just did a tune up with a fuel filter and new wires. Barely driveable. Haven't done a compression test yet. Low acceleration, have to keep it at high RPMs or it might stall, hesitates, with a fuel smell. Any ideas?
 

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You nailed it jpgrl6992.
My suggestion is to do a compression test before anything. In the course of getting ready for the compression test, make absolutely certain that each plug wire is connected to the correct spark plug.

Let us know what you find.

Good Luck, L.M.
 

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So was this like this after the tune up, or you bought it like this? That could/would make or break the diagnosis.
 

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Discussion Starter · #4 ·
Nope, I've had it for almost 20 years. Just replaced the radiator, water pump, thermostat and housing a few weeks ago.
 

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Nope, I've had it for almost 20 years. Just replaced the radiator, water pump, thermostat and housing a few weeks ago.
That didn't answer the important part of the question...

Did the problem occur randomly OR did the problem occur immediately after you worked on it?
 

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I suspect switched spark plug wires. That's what makes the most sense to me.

The firing order is 1-3-4-2 in a clockwise order.

Good Luck, L.M.
 

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Ashamedly I will admit a couple weeks ago when I installed a new distributor I screwed up twice. First I switched 3 & 4 plug wires. Once I figured that out I found I had it a tooth off. Overconfident? guess so, after wrenching for 45 years you think you can do stuff without looking. Stuff happens, check and recheck.
 

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Ok in that case I'd be looking at compression numbers, fuel pressure, cracked distributor cap, function of fuel injectors, clogged catalytic converter...
 

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300K..you got some good service on that one. Id say its time for a compression check as its likely just tired.
 

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Discussion Starter · #12 ·
Cylinder 2 & 3, was told that was a blown head gasket. Which really sucks. Fuel pump is working, injectors are working. My poor Jeep. I dunno whether to get it rebuilt or get a new motor. It was a birthday gift from a now deceased friend
😞
 

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Pull the head and put a head gasket on it....
Not that big of a job
 

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With 300,000+ miles on that motor I would start looking at the cost differences between rebuilding it, used motor, and new re-manufactured motor.
 

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Who told you it was a blown head gasket? Did they do a compression test or does the oil look like chocolate milk? If they did a compression test, what were the numbers?

Used motors on any old vehicle are a crapshoot.
If your head gasket is truly blown , at 300K, I wouldn't bother with trying to repair the motor. I'd replace it with a re-manufactured motor. That's if it's truly a bad head gasket.

Let us know how it goes.

Good Luck, L.M.
 

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I agree with LMac, check out the oil. Any white smoke coming from the exhaust; engine running hot or low coolant? Even any signs of coolant leaking around the head? I'm not sure I would default to a blown head gasket if the engine is missing on 2 cylinders. Sounds more like a "spark" issue to me (you need air-fuel-spark to run an engine), as in switched wires; bad plugs; distributor; etc.
 

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Used motors on any old vehicle are a crapshoot.
I agree but there are still low mileage used motors out there with a 30 day warranty for $600-$800. If a person doesn't have the money to rebuild or $2200+ for a re-man it's an option.
I stumbled on a supposedly fresh rebuilt 2.5 on Craigslist for $250. Seller didn't have documentation of anything said I could hear it run. I passed on it, wish I would have at least went at looked at it now even though I don't need it yet.
 

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Discussion Starter · #19 ·
Changed the wires, plugs, rotor, distributor was clean. Coolant is good. Had spark until I changed the plugs. Wires are not crossed, did them like my father taught me - one at a time.
 

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Every post you make seems less and less clear.

"Had spark until (you) changed plugs" makes it sound like you may have a spark plug or wire problem...

WAS A COMPRESSION TEST DONE?
If so what were the numbers?
And was a leakdown test done next to confirm?
 
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