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I have a 1998 4x4 Ranger ext. cab with a 3.0. I was leaving work, stopped at a traffic light and noticed it was ideling a little rough. I went about another 3 miles and noticed a clicking or ratteling coming from engine compartment. hoping it was only the exhaust rattling, I kept driving and within another mile i lost a ton of power pulled over and it died. Got it towed home waited over night started it up in the morning. It was running rough but no "clicking". Checked the oil i was 2 quarts low so added oil and drove it to my dads house to work on it. About 2 miles and it did the same thing. I had a diagnostic check and it came up with a misfire on 5 and 6 cyl. pulled the plugs and half of them, the electrodes were completely burnt off. I also noticed one of the boots were ripped and it was arching to the engine. I replaced all plugs and wires, no help. Replaced the ignition coil (distributor) and still no help. I checked the compression last night, only 2 cyl. were up to spec pressure and the rest were around 30 psi and one was about 5 psi. Are stuck valves ever an option or are they prob toast. I dont think its in the bottom end because i have run low on oil before and slipped a crank bearing on a previous rig and it sounded completely different. My dad thought it was a case of "spark knocking" but now he's conviced its the piston rings. Im going to run another pressure test(forced air into the cyl.) to see where the leak is. If it turns out my motor is "f"ed what can I swap it with. I have found a couple of 3.0's and 4.0's but they are newer. I would kinda like to stuff the 4.0 in there but i know stock the gear ratio is a little differant but does that matter and is it all a direct fit, or do i need the donor computer and/or wiring harness. Any imput would be appreciated. It sucks not having my truck.
