New Plugs and wires, BIG CHANGE

[sr139fox]

I have 155,000 miles on my 2001 Gen 2 sport trac. I think my plugs and wires were original. I changed the Autolite Double Platinum (APP103) with Motorcraft SP-500 Fine Wall Platinum and new Motorcraft WR5944 Spark plug wires. The old plugs had gaps ranging from .051” to .072”. I did not mark where they came from. I did not gap the new plugs because I was afraid to damage the new smaller electrode. My hi-way millage went from 18MPG to 20 MPG and around town increased. I can feel more power from the engine. Probably getting about 50 more miles per tank.

Right bank was a PIA with a hard line in the way and the heater core there. Did the right entirely from the wheel well. Left bank can be done from the top. Much easier. All plugs were tight coming out. I was sure I would have to run a tap dome the threads, but I did not have too. Put anti seize on the plugs and Di-Electric grease on the new plug wires. Took about 3 hours, took my time.

I cleaned the Throttle body, the IAC valve, and replaced the PCV valve with a new plastic line and elbow.

I want to thank everyone in the group that posted on these subjects. I read many post and reviewed some pictures. Can’t remember who they were, But thanks a bunch.

Dave P.

 

[swshawaii]

OEM plugs were Motorcraft AGSF22FM. From the factory the banks had slightly different plugs because of the EDIS "wasted spark" ignition. Motorcraft SP500 Finewire ground electrodes should not wear nearly as fast as the previously replaced Autolite APP103 plugs. Sounds like you did a textbook job and it's paying off as we speak. Also smart to clean the IAC and TB, they make a big difference and should be considered preventative maintenance. Keep ALL the fluids clean and it wouldn't surprise me if you easily get to 300k.

 

[sr139fox]

Thanks. The forum was a big help in doing the work. Without it I would be lost, even though I am a wrench turner.

I plan on keeping the truck a very long time. I'm from PA and know about rust. Here in eastern NC, there is no rust. I have a rust free 2001 Sport Trac. Did the front end last month. Need to track down that pesky oil leak. Looks like the valve covers are leaking. Next year project is the body mounts.
Dave P.

 

[Carpin]

OEM plugs were Motorcraft AGSF22FM. From the factory the banks had slightly different plugs because of the EDIS "wasted spark" ignition. Motorcraft SP500 Finewire ground electrodes should not wear nearly as fast as the previously replaced Autolite APP103 plugs. Sounds like you did a textbook job and it's paying off as we speak. Also smart to clean the IAC and TB, they make a big difference and should be considered preventative maintenance. Keep ALL the fluids clean and it wouldn't surprise me if you easily get to 300k.

My ST is about to reach 120K miles, I noticed my gas consumption is up, I'm planning to change the O2 sensors and the spark plugs (cables included). Do you have any recommendation on spark plugs and cables (besides the motorcraft SP500) somebody recommended the NGK iridium IX. what about the cables? any specific brand?

 

[swshawaii]

^ Any reason you don't want to use the MC SP500 plugs? Availability? Price? Can honestly say they are the only plugs I've NEVER heard a complaint about with the 4.0 SOHC. In a pinch I would use the Autolite XP103 Iridium or any Autolite 103 series plug. If aftermarket is your only choice the NGK 7164 (IX) is probably a good substitute. My original plugs came out very screechy after 60k coated with rust and had gaps up to .75 caused from center electrode wear. A very thin coat of nickel or copper anti seize is highly recommended, especially with the SOHC's aluminum heads. Regarding plug wires, that's a personal preference. Trick with aftermarket is finding a set with the correct lengths, not one size fits all. Do it right and you're good for another 70k minimum. GL

http://www.rockauto.com/en/catalog/...park+plug,7212?a=Referer+www.google.com+URL+/

DO I NEED TO SET THE GAP WHEN INSTALLING A NEW SET OF PLUGS?

A: Maybe. A spark plug part number might fit hundreds of different engines from many different manufacturers. Although the NGK factory will set the gap to a preselected setting, this may not be the right gap for your particular engine. The incorrect plug gap for your engine can contribute to a high rate of misfires, loss of power, plug fouling, poor fuel economy and accelerated plug wear. It is always best to check the gap against the manufacturer's specifications. If adjusting the gap on fine wire or precious metal plugs such as platinum or iridium, be very careful not to apply any pressure or prying force to the fine wire center electrode or insulator as they can be damaged. The gap should be adjusted by only moving the ground electrode.

https://www.ngksparkplugs.com/about...et-the-gap-when-installing-a-new-set-of-plugs

 

[Carpin]

I think I'll go with the SP500's, what about the cables? the motorcraft WR5944 are good enough for my ride? j

 

[swshawaii]

Motorcraft seems to be the preferred choice. Strange, but I've heard of the Autolite's being incorrect lengths.
CHECK the build date on your door sticker or use FordEtis. Different MC wire sets for before and after 7/24/2000 dates.
http://www.rockauto.com/en/catalog/...4.0l+v6,1366680,ignition,spark+plug+wire,7224

Click vehicle, enter VIN, and click minor features.
https://www.etis.ford.com/

 

[mt hwy]

Been watching this thread. I've recently purchased a 2005 with the 4.0 engine, going over it here and there. Runs well but even though do any of you still recommend I clean the IAC as preventative maintenance? ... if so where is it and what is the basic procedure? Also, I looked at one easy to get to plug, it looked clean and burning perfectly, maybe some miles on it but hard to tell, with 138K miles I assume they been changed at least once - is it worth the time and effort to replace and call it good on the plugs? Thanks .... and where do I get those wheel center cover Ford stickers!!??

 

[mt hwy]

Ok, just googled it and watched half dozen IAC cleaning procedures, think I understand that one.