I am looking to change out my sparks plugs on my 97 4.0 litre. It runs rough when cold. I want to use the autolite double platinums and Advance auto has 3 or 4 diffrent part #'s for the DP's that say they fit my Mazda. How do I know which ones to get? some of them are black and some silver. I was looking at the 458 DP's. Are those good?

thanks,

Mark

 

Consider using the specified Motorcraft or Autolite fine wire double platinum plugs.

As spark gap is always opening up with time, use a Wire gauge to Carefully set the spark gap to to the min side of spec, by Slowly sneaking up on the correct gap. Don't pull the gauge through a tight gap, so as not to damage the fine wire center electrode, or platinum pad on the ground sidewire.

I brush a very light coat of Permatex high temp, nickel loaded, anti-sieze compound on the plug threads & torque them to the Low side of spec, to allow for the lube effect of the anti-sieze so as not to over tighten them.

I also butter on a light coat of a good dielectric grease, like GE, DowCorning, Permatex/Loctite, to the plugs outer ceramic insulator & inside the plug wire boots on both ends, to prevent flash over on those damp dewey morning starts, or rainy day drives.

The fine wire plugs on my rides offer up faster cold starts year round, making it easier on the battery, starter, alternator, fuel pump, ignition system & ultimately my wallet, as the spark gap stays in spec longer & they work better & last longer in our waste spark ignition system.

A bunch of thoughts for consideration, let us know how it goes.

 

thanks for the response. My problem is that
Advance auto says there are 4 different double plantinum Autolite plugs that are "specified". Just asking if all are good and why there are so many or which one to get.

mark

 

I agree with what Pawpaw says completely. As far as which one to get, you need the Autolite APP103 which is a double platinum plug with a .54 gap. You can and should adjust to the proper spec when installing. If you want an even better plug, while not necessary, you can use a Autolite XP103 which is a fine wire Iridium. If the store you are selling is not listing either, go elsewhere. These plugs MUST be of the proper material and heat range. Alternatively you can use NGK 5598 which is a fine wire double platinum, or NGK TR6IX which is an Iridium. Do not use Bosch or generic plugs, which generic including Federal or Standard, store brands, etc. Use only Motorcraft, Autolite, or NGK for the best results. Replace all the plugs at the same time if you are going to replace them, I've seen all to many people only replace 1 or 4 of them, and leave the most difficult to access ones in place.

 

For our waste spark ignition system 4.0L pushrod engine, Ford now specifies the finewire iridium enhanced center electrode, with platium pad sidewire plug SP-500/AGSF22FM.

Autolite also makes Motorcraft plugs, so their fine wire offering XP-103 is also a choice & Autolite has rebates on their plugs, so check out their website.

Also here are some AAP discount codes that you might find useful, to help lower the plug cost. Advance Auto Parts Coupons & Deals, Advance Auto Parts Online Coupon Codes, Discounts

Also promo code P20 is still in effect I believe, so if your not buying a lot, it'll offer a 20% online discount on any amount ordered.
If you order on line & pick up in the store, no shipping charges, so that lowers costs too & is how I usually do my online business.

More thoughts for consideration, let us know how it goes.

 

Here is a mini spark plug tutorial listing of spark plug design & uses I've made note of, that might answer some of your questions about why so many plug types are listed on autoparts stores web sites. https://www.ford-trucks.com/forums/1...-tutorial.html

 

thanks for the info. I will look it over.