Install Plugs, Wires, and Pack

RAK

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Ok, guys, to most of you this is a no-brainer--but for me, I'm not too tech savvy when it comes to mechanics. I want to replace my old spark plugs and wires, and the old coil pack.
Which is the best and safest way to do this (what are the steps involved)? My Mustang is 17 years old and I thought it's time to switch out. I've purchased NGK plugs, wires, and pack to replace the OEM items.
Thanks in advance for your input, recommendations, and advice!
 
Keeping yourself organized is of paramount importance whether you're new to this stuff or familiar with it.

Don't buy the wrong plugs. Your Mustang may have a "waste spark" system which requires double platinum plugs. Lots of vehicles are particular about the plugs.
This is not the time to "modify" anything.

I don't know your engine so tooling (ratchet wrench handle, socket, extensions) may need to include universal joints or even a shallow socket to reach.
>>Do one plug at a time. Keep your twisting motion square to the plug. Run the new plug in by hand as far as you can.

Sometimes a short length of stiff hose / tubing can be used to increase reach if needed. Land the new plugs using the correct amount of torque.

Some people use anti-seize on their plugs others don't. Some plug manufacturers state NOT to use anti-seize on their plugs.
 
watch at least 3 youtube videos specific to your engine. Take your time, replace your plug wires 1 at a time so you know they are going to the correct place.
 
Do one wire at a time so you don't get them mixed up. As for the new coil, make a note on the towers which one goes to each cylinder for when you swap the coil over. I forget the access on those V6 Mustangs, but you might have to take the upper intake off to give you a bit more access depending on how skinny your arms are. Also don't forget the dielectric grease on the boots of the wires.
 
I would also suggest taking pictures before starting and labeling the current wires and locations on the pack so you which wire goes to which plug.

label new cap as well and confirm it matches old one .

Things like that.

The labeling could be as simple as masking tape and sharpie marker.
 
It's pretty straightforward. Sometimes it is easier to make labels for the plug wires noting which cylinder each goes to, when replacing the coil pack.

Sometimes it is easier to get at spark plugs with the wheel and wheel well liner off.

It is usually easier to have a variety of socket extension lengths and/or swivel ratchet... varies per vehicle.

You don't need anti-seize on standard nickel plated (chrome looking instead of oxide black) plugs. That's why they are nickel plated.
 
Find and/or draw a diagram of which coil tower is wired to which plug. Double check by tracing the wires on the car. Be sure you know that fully before removing any wires.

Arrange the new wires by length then match up the best fit with each old one as you take it off. Don't be surprised if they're all too long. Somehow aftermarket wire makers are unable to figure that out.
 
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If you have compressed air available, blow around each plug prior to removal to prevent any dirt from falling into the cylinder.
 
I just worked on a 99 Stang 3.8. if it's the same, it's easy to access.
I would like to open this up to the group though: we replaced the existing Motorcraft coil (which was working) with one from a junk yard. (it was a non-OEM) it turns out that the junk yard coil pack was defective - the first coil was open. now, suddenly, the driver circuit in the ECM stops working. Logic would seem that the defective coil "took out" the driver in the ECM.

Is this plausible? Does one really want to randomly replace a coil pack.
 
Coil packs generally aren't maintenance items. I would not replace one that is working unless it had physical problems like cracks or burned terminals from a bad wire losing contact.
 
Originally Posted by tomcat27
I just worked on a 99 Stang 3.8. if it's the same, it's easy to access.
I would like to open this up to the group though: we replaced the existing Motorcraft coil (which was working) with one from a junk yard. (it was a non-OEM) it turns out that the junk yard coil pack was defective - the first coil was open. now, suddenly, the driver circuit in the ECM stops working. Logic would seem that the defective coil "took out" the driver in the ECM.

Is this plausible? Does one really want to randomly replace a coil pack.


Yes, I have seen coils take out the coil driver in a PCM.
 
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