Autolite AP764

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Aug 20, 2006 | 08:22 PM

jjlrrw

Thread Starter

Mountain Pass

Joined: May 2005

Posts: 203

Likes: 2

From: West Michigan

Autolite AP764

'01 F150 4.6L, I have a MisFire #8, swapped COP, replaced all 8 plugs with autolite AP764, it ran better for a very short time then started to miss again and after 100 miles or so CEL "Misfire#8" again.

Are these plugs okay to use?

Should I start looking at the injectors?

Thanks,

Aug 21, 2006 | 05:22 PM

steve(ill)

Hotshot

Joined: Jul 2005

Posts: 11,931

Likes: 180

plugs can go bad. i migh tbe tempted to buy one plug and install in #8 and see what happens.

Aug 21, 2006 | 05:58 PM

BlueOvalFitter

Cargo Master

Joined: Aug 2002

Posts: 2,013

Likes: 6

From: Cajun Country

Try using Motorcraft plugs.

Aug 21, 2006 | 08:34 PM

jjlrrw

Thread Starter

Mountain Pass

Joined: May 2005

Posts: 203

Likes: 2

From: West Michigan

I replaced the plugs with the motocraft same misfire, CEL has not yet came back on but still runs the same.

Then...

I than decided to unplug the wire to #8 injector truck ran a little worse and the CEL came on, I than plugged the #8 injector back in and unplugged #6 injector, truck seemed to run about the same as when I unplugged #8.

I am thinking #8 injector is about 75% shot??? I am going to pick up an injector and a set of o-rings for the other three injectors on that side and see what happens. I wish it was on the other side 1-4 as that #8 is way back in there.