Which spark plug gap should I use

ok,i know someone who just went through this a while back.that plug AGSF-34EE is discontinued! the SP-504 is the correct plug for your truck.the other numbers and letters are AGSF-34FM.if you still have the AGSF-34EE in your truck,when you take em out you will see that they only have FIVE threads on the spark plug..the AGSF-34FM has TEN threads on the spark plug.they are NOT to long.if you hold the 2 plugs sided by side,they seal off at the same point/distance.now as far as the gap being .044 or .054,you need to look at your emissions label,manual and go to the Motorcraft website and look it up there also,and i'm sure there will be more help on this today.ALSO>>have you ever changed the plugs in one of these ford trucks before?

The AGSF-34EE is the plug referenced in the service manual which is why it's cited. The old plugs that were actually in the truck are Bosch+2 platinum. I already took them out and they look to be in good shape. They were in the truck for 6 years and were doing great until I got a misfire code on cylinder 5. That plug had a carbon track on it so I replaced it along with the wire. Truck ran better but still not completely smooth. It did run smooth at idle. I decided to replace all the plugs and gapped the new plugs to .054. I have since learned this is the correct gap for the plug even though the preset is .044 from Motorcraft. The new plugs are not running smooth at all - not even at idle. That's what prompted me to question the gap. I checked all the connections, they seem solid. All plugs were torqued to spec., at 15 ft-lbs. I only used a very thin film of anti-sieze on the threads so nothing got on the end of the plugs. I listened to all the injectors and they sound fine, uniform and consistent. So now I'm stumped. :(

i don't see how it ran with Bosch plugs in it! i know people with 8 cyl who tried them and took em back out,and went with MC... i was going to say .054,but i was gonna leave that to you.i have a 2000 F150 4.6L and my manual says .054 and reference the emissions label under the hood.on another page under engine data it states .052-.056 so really it don't have to be perfect..044 would maybe be better on cold start ups.my manual also says the gap on the 4.2L(2000 model)is the same as the 4.6L,and 5.4L(.054). i think,if i remember right,when they first came out with the 4.2L Ford specified two different spark plugs for that engine, so you'd have different plugs on opposing cylinders. They've since updated the plug to where there's only one plug, and it'll work for either side of the ignition. you have wires on your engine where i have the COP'S on mine.i don't see how it ran with Bosch plugs in it! i know people with 8 cyl who tried them and took em back out,and went with MC... i was going to say .054,but i was gonna leave that to you.i have a 2000 F150 4.6L and my manual says .054 and reference the emissions label under the hood.on another page under engine data it states .052-.056 so really it don't have to be perfect..044 would maybe be better on cold start ups.my manual also says the gap on the 4.2L(2000 model)is the same as the 4.6L,and 5.4L(.054).i hope you used a wire type gauge to re-gap those Finewire plugs? i think,if i remember right,when they first came out with the 4.2L Ford specified two different spark plugs for that engine, so you'd have different plugs on opposing cylinders. They've since updated the plug to where there's only one plug, and it'll work for either side of the ignition. you have wires on your engine where i have the COP'S on mine.you will also have different opinions about using anti-seize on the plugs.Ford says No,they have a special coating on the threads.i have a friend who works on these engines a lot,and he says YES? i've done it both ways,and the first ones i took out 73,000 miles after i bought the truck had NO anti-seize on them,and also had one odd ball PLUG in #3>AWSF-32EE and the others were AGSF-32FM which is the replacement plug for the 32EE plug? i won't run em no 100,000 miles again.some of my old ones were on as much as .082!!! never showed any symptoms,still looked good except for that Mike Tyson Gap in it! i found some original 32EE plugs on e-bay a long while back.some guy at a dealership listed em for $27.99 and free shipping.i e-mailed him to make sure that his listing was for 8 plugs as described.he e-mailed me back and said NO,that's for ONE! i put a keyboard cussing on that boy that his mammy couldn't get off with a brillo pad!

The plugs were Bosch+2 platinum and it ran really great for many years. This recent problem is giving me fits and I thought I was being prudent with all Motorcraft plugs and wires. So it goes.

some how i double posted half of my long story above? hey, if it ran better with the Bosch plugs than it does with the Motorcraft,and you got the funds,change em to what runs the best for you!

Responses can be edited so if that happens it can be corrected. For my truck problems, I'm thinking I should replace the coil to see if it helps. If not then I'll just start reversing what I've done, putting back in the old stuff until it runs again.

yes,but it can only be edited UNTIL someone replies to it,then it can't be edited any longer.depending on how big of hurry you're in,the Motorcraft ignition coil Part Number DG-532 is $108.00 plus tax at local parts houses. a guy on e-bay is selling that same MC coil for $60.95,free shipping..eBay item number:281105849453(trueblueautoparts)with a 99.7% Positive feedback..i have bought from him before.by the way,you didn't pull all the wires off at one time and maybe cross one of them,did you? no back firing right?

Thanks for the edit info, I did not know that limitation. Thanks for the info on the coil. I did order an MC coil but I went through Walmart for $64 and free shipping. I should have it Tuesday. The parts stores don't stock it and their prices are outrageous. I did the wires individually and double / triple checked for order against the manual. They are in the correct position and all connected firmly. I disconnected the battery to clear the computer in hopes it would learn some thing new was installed and now I am getting some backfiring.

i know the parts houses are sky hi! 400% mark up.i know lots of people that work at em. take for instance that little pack of grease that Autozone tries to push on you when you buy a battery,a bulb,a coil,an ignition control module,a hose,a head light.they push it because it is the most profit making item in the store.they have .05 cents in it and sell it for $1.49 a pack? that's not hear say,it's a fact!.as far as your back fire,you may have cracked a plug,injector may be bad,intake gasket leak,vacuum leak.get you a can of starting fluid and spray around the intake(carefully),see if the idle changes,also spray the vacuum hoses(carefully)pcv valve hose also and hope you find it.if it's none of that,then maybe it's the coil pack?hope it's not the PCM!

I got a mad coil pack and msd iridium plugs gaped at 054 runs good by the way is a4.2

Runs great fre flowing muffler 2 less catalytic converter header's and a cold air intake I could beat a 4.66