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3.0 Engine Misfire on 2001 Ford Taurus

I had a consistent misfire on this car and finally got a P0301 trouble code. I installed new Autolite AP 104 plugs and wires. Now, when I start the engine. it runs perfectly. But when I put it in gear, it misfires. After a minute or so, the misfire clears and the engine runs perfectly. I have not received another trouble code. One thing I did notice is that the plugs I took out (Motorcraft AWSF 32P) had a much larger gap than the .044 the associate at AutoZone set the new plugs to. Sure would appreciate some suggestions. Thanks.

The plug gap grows wider b/c the electrodes wear away the more miles driven. If it gets too wide the engine will ping and misfire. That can also damage the coil(s). B/c of the wide gap you noticed in the plugs you removed, suspect a damaged coil.

Thanks for that reply. I appreciate it!

My taurus plugs had .090 gap when i had my misfire code. Than the coil had to be replaced a few months later. But I have the 12v motor.replace ur PCV elbow too. Did u take off the wiper cowl to remove the rear plugs? U didn’t say so I assume u have 24v motor.

Thanks for your reply. I am unsure of your reference to the “PVC elbow” and “12v motor”. I did not have to remove anything to remove the rear plugs. Thanks again for your reply.

12 valve is Vulcan motor. 24 v is duratec. Vulcan has 1 coil. If u changed plugs ur self, u might be aware of that. Some folks are blissfully ignorant. Which is not the same as not smart.

If OP changed the rear plugs without removing anything else, I’m thinking Vulcan motor

I’m also thinking Vulcan, because it was by far the more common motor in 2001

Any chance this is an idle problem (vacuum leak, Idle Air Valve, etc) problem? It sounds like you’re referring to a stumble due to the idle dropping a bit low when you engage the transmission.