2 Cylinders not fireing
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2 Cylinders not fireing
70 F100 Ranger 2WD 360 v8 2v
I have 2 cylinders on the passenger side, closest to firewall, of the engine that are not fireing. I have new Autolite platinum plugs, new points and condenser, but I havent replaced the wires or the cap and rotor yet. The cap and rotor look pretty good though. Am I possibly looking at a rebuild here??
I have 2 cylinders on the passenger side, closest to firewall, of the engine that are not fireing. I have new Autolite platinum plugs, new points and condenser, but I havent replaced the wires or the cap and rotor yet. The cap and rotor look pretty good though. Am I possibly looking at a rebuild here??
Posting Guru
Joined: Feb 2007
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From: Pittsburgh,Pa.
I'd suggest a compression test first. Two adjacent cylinders that are not firing could be the result of a blown head gasket.If the gasket failed between the cylinder bores it would allow compression pressure to be pushed back and forth between them.Hope this helps.
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Joined: Jul 2006
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why are you running platinum plugs? Platinum plugs may be the problem.
Given equal gaps the specialty plug will produce spark that is less powerfull. Yes the conductor is more efficient, but with a stock ignition system the voltage required to produce a quality spark is just not there. The specialty plug works great for engines with good voltage to produce enough to jump a gap large enough to make them work, but will have a very weak spark with a stock system, and will produce less power than a traditional plug.
Given equal gaps the specialty plug will produce spark that is less powerfull. Yes the conductor is more efficient, but with a stock ignition system the voltage required to produce a quality spark is just not there. The specialty plug works great for engines with good voltage to produce enough to jump a gap large enough to make them work, but will have a very weak spark with a stock system, and will produce less power than a traditional plug.
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Thanks for the info. I was originally using stock plugs and thought that the platinums would be better. I didn't know about needing to upgrade the rest too. I want to upgrade the ignition system anyway so noe I have a good excuse. It was doing this prior to changing the plugs anyway so I don't think that was the problem.
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From: Westminster, Colorado
Originally Posted by 75F350
why are you running platinum plugs? Platinum plugs may be the problem.
Given equal gaps the specialty plug will produce spark that is less powerfull. Yes the conductor is more efficient, but with a stock ignition system the voltage required to produce a quality spark is just not there. The specialty plug works great for engines with good voltage to produce enough to jump a gap large enough to make them work, but will have a very weak spark with a stock system, and will produce less power than a traditional plug.
Given equal gaps the specialty plug will produce spark that is less powerfull. Yes the conductor is more efficient, but with a stock ignition system the voltage required to produce a quality spark is just not there. The specialty plug works great for engines with good voltage to produce enough to jump a gap large enough to make them work, but will have a very weak spark with a stock system, and will produce less power than a traditional plug.
As for cap rotor and plug wires....I replace them once a year, regardless of condition.....every 6 months on my 74 Beetle......plug wires, especially, are prone to tiny cracks that allow the voltage to "leak" over time.....
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It smoked like a fog machine when I first got it but it had set up for about a year to a year and a half. I added a can of engine restore to the oil and have ran the truck two or three times a week since I got it and have noticed no smoking. I think the timing is off a little also because it fires back through the carb occasionally, usually when taking off from a dead stop.
Thanks for the help so far. I'll change the cap/rotor and the plug wires and get back with an update.
Thanks for the help so far. I'll change the cap/rotor and the plug wires and get back with an update.
