Does brand of sparkplugs really make a difference?

[Spurred98]

'98 f150 4x4 4.6 ltr. I've got a miss that I belive is spark related. I changed the plugs and put in Autolite APP 104 plugs. It still missed so I changed the plug wires. I put in a set of wires from Napa and truck runs a lot better but seems sluggish. Should I replace Autolite plugs with Motorcraft Platinum original plugs? Is there really that much difference between sparkplugs or is this just Ford wanting to sell me original parts at hiked up prices? Any replies are apprieciated! This is a great forum!

[MT-2500]

You will find the motorcraft platinum that the book calls for will work the best in it.
Shop around a little for the best price.Sometimes dealer and sometimes a parts house will give you the best price. Should be around 5-8$
Check you spark output to the plugs on it. Could be weak coil or even a bad new plug wire.
Also if you have a scanner check for what cylinder is missing and zero in on that cylinder.
MT-2500

[MT-2500]

To add if all else fails have the dealer run your vin for any tsb's that may pertain to your engine miss or rough idle. There may be one that requires a PCM flash or 02 sensor update.
TSB no. 97-21-13 on ones built threw 11/97
Any check engine lights or codes on it?
MT-2500

[Spurred98]

MT2500, while I'm not sure what a TSB is, I did put the original Motorcraft sparkplugs in it. I went to my nearest Ford dealer and bought plugs for $5.35 each! That surprised me. Puting the new plugs in, I used the di electric silicone that came with the plug wires(I should have used it when I first put plug wire on, but didn't). When I went to pull plug wire No. 8 it came right off way too easily. After changing all plugs and making sure I heard the clicking sound when I put plug wires on plugs, I started the engine up and went for a ride. Zero misses at all road speeds. This last weekend I went to my cabin and put on about 200 miles and when I'm at a stopsign I have to look at the tach(with the radio on)to verify the engine is running! It's that smooth. So by you recommending original plugs, I found my screwup. Thankyou very much, MT 2500

[MT-2500]

You are welcome.
And Thanks for posting back and letting us know how it went.
Your dealer is actually cheaper on some things.
And always use the oem motorcraft plugs on a ford.
Just like AC delco for a GM car or ttruck
They are the ones made for it. The newer they get the more touchy they are.
Motor craft allways matches the heat range and the type of plug they need.
Other brands do not have or match all of all of the right heat ranges and will sometimes give problems.
If it is running good do not worry about any TSB's some times you need them and some times you do not.
Good luck and thanks for posting back.
MT-2500

[way2old]

Agree with you 100% MT2500. I am a firm believer in OEM plugs. Good call.

[MT-2500]

Thanks Way2old
MT-2500
Alias Sherlock/Crunch

[way2old]

AHHHHHH, the plot thickens!!

[badasstour]

any platinum plugs will make it run better, i have a 96 tour,and i put in bocsh platinum 4 ,cause i had a little miss in it,and they took it away.

[Cait Sith Cat]

5.35 a plug? BS!!