Spark plug wires?

Topic: Spark plug wires? (Read 4742 times) previous topic - next topic

Spark plug wires?

March 13, 2015, 10:39:58 AM

Hey there,

Yesterday, I changed the spark plugs in my '86 Cougar GS. It only has a little over 16,500 miles on the original 5.0L V8. It wasn't driven much by the previous owner who had bought it new and kept it until she passed in 2010. The spark plugs were the original plugs that came with the car. Total night and day difference in performance!

My question now is, should I replace the spark plug wires since they're the original wires?

Thanks in advance!
Tommy

Spark plug wires?

Reply #1 – March 13, 2015, 10:54:00 AM

Its fairly common to do spark plugs, wires, distributor cap + rotor all at once

Spark plug wires?

Reply #2 – March 13, 2015, 11:15:05 AM

Please excuse my ignorance, never having replaced either, but what's the main reason for replacing the distributor cap and rotor? Again, I'm sorry for my ignorance. I've heard plenty of people talk about replacing plugs and wires on their cars, but not so much distributor caps and rotors.

Spark plug wires?

Reply #3 – March 13, 2015, 11:48:30 AM

No worries! We can all learn from each other! So from what ive been told, when the spark jumps from the rotor to the points on the distributor cap it carries a VERY small amount of metal from the rotor to the point on the cap. Over time you can actually build up material on those points

Spark plug wires?

Reply #4 – March 13, 2015, 11:50:30 AM

Quote from: thetommyboy2k;445998

Please excuse my ignorance, never having replaced either, but what's the main reason for replacing the distributor cap and rotor? Again, I'm sorry for my ignorance. I've heard plenty of people talk about replacing plugs and wires on their cars, but not so much distributor caps and rotors.

At 16K mi if the wires, cap, & rotor appear in good condition I wouldn't replace them... Why?? These components do deteriorate slightly with age, but usage(25Kv traveling through them, under hood temps of 200* plus, etc) is far more more the determining factor...

Spark plug wires?

Reply #5 – March 13, 2015, 01:00:13 PM

Quote from: TurboCoupe50;446000

At 16K mi if the wires, cap, & rotor appear in good condition I wouldn't replace them... Why?? These components do deteriorate slightly with age, but usage(25Kv traveling through them, under hood temps of 200* plus, etc) is far more more the determining factor...

The wires looked ok, but I'm wondering if they need to be replaced because one of the plugs I pulled out (furthest back, left side)... the white part of the plug actually had crumbled. I'm thinking it's a good possibility the plug didn't even fire or just barely did. When I ran the Cougar with the old plugs, I'd have to push the accelerator a fair amount to get it to go, as if the Cougar had a good bit of hesitation. It was missing quite a bit as you could feel it during idle. Felt almost like a rumble. Plus, the gas mileage seemed horrible (yes, I know it's a V8), but it seemed like the gas hand would move more than it should just on a short run. I changed the plugs with new Motorcraft plugs and it was a night and day difference in performance. No lag and from what I can tell, no missing. Just wonder if new plug wires would make even more of a difference. I haven't checked the cap and rotor. This car was babied... garaged, taken out once in a while, but nothing major. It's as close to driving a then new Cougar as I believe a person could get.

Spark plug wires?

Reply #6 – March 13, 2015, 01:02:53 PM

My first 86 had around 200k miles on original spark plugs. I replaced them and saw no difference. They even said ford motorcraft 1985 on them.

Take the cap and rotor off. If you see anything that looks corrided, replace it, or try cleaning in with a wire brush.

Spark plug wires?

Reply #7 – March 13, 2015, 02:27:15 PM

Oops, ment wires not plugs,

Spark plug wires?

Reply #8 – March 13, 2015, 02:43:50 PM

I'd definitely replace the wires, but the electrodes on the cap and the rotor, unless they're "fuzzy" looking from buildup, I'd just lightly sand them and reuse them.

If the plugs were bad enough that you felt and immediate difference, likely the wires are in need of replacement. The rubber/silicone will crack and dry over time and you'll see sparks jumping from them. Start it in the dark sometime with the hood open...with bad wires, you'll see a lightning storm, LOL.

Spark plug wires?

Reply #9 – March 13, 2015, 08:10:55 PM

If you can get the car where it is really dark you can see what ThunderbirdSport302 is talking about. Pop the hood and fire the motor up. If the plug wires are bad you will see indications of blue spark where the plug wires get close to metal.

Have you changed the oil and replaced the fuel filter? Unless you have paperwork stating that this was done I would do it for a piece of mind. The other thing you may want to do is put some fuel additive in the tank just in case there is some water in there from the car sitting. I would also look at having the transmission serviced (filter change only do not have it flushed) and I might even go as far as servicing the rear end with a fluid change as well. All just preventative maintenance items due to the car sitting so long.

Darren

Spark plug wires?

Reply #10 – March 13, 2015, 10:18:47 PM

When you replace the wires get a set of Motorcraft wires. The cheap parts store ones suck. As others have said I would replace the wires but leave the cap and rotor alone if they look fine.

Spark plug wires?

Reply #11 – March 14, 2015, 08:58:21 AM

Quote from: Aerocoupe;446014

If you can get the car where it is really dark you can see what ThunderbirdSport302 is talking about. Pop the hood and fire the motor up. If the plug wires are bad you will see indications of blue spark where the plug wires get close to metal.

Have you changed the oil and replaced the fuel filter? Unless you have paperwork stating that this was done I would do it for a piece of mind. The other thing you may want to do is put some fuel additive in the tank just in case there is some water in there from the car sitting. I would also look at having the transmission serviced (filter change only do not have it flushed) and I might even go as far as servicing the rear end with a fluid change as well. All just preventative maintenance items due to the car sitting so long.

Darren

I would've went outside and started it last night, but it was raining too much and this morning, it's still raining too much.

I know the oil and filter was changed, but I'm going to change it again sometime soon. I've had the car since either late October or November, and I've only put 400 miles on it since I've had it. I haven't changed the fuel filter or any of the other things you mentioned. Just don't have that kind of money right now. I take care of my Mom, who's 81, and I've been on a leave of absence from my job. She had to go into the hospital due to a uninary tract infection (wasn't too serious, but antibiotics we had given her prior to her going into the hospital did nothing due to the bacteria that was in the UTI). I'm going back to work on the 21st, so I have to watch my pennies.

The time period I'm really unsure about as far as how long it sat at a time is when the lady's son had the car from 2010 until it was traded at a dealership in Lenoir last year, which was in turn traded to the dealership I bought it from. I figure when his Mom had the car, although she didn't put a lot of miles on it, I figure it was taken care of. I have no doubt it was garage kept. I took the Cougar to Campbell's Transmission in Inman (anyone who lives in Spartanburg and especially in the town of Inman in South Carolina... Mike Campbell does awesome work and is an honest person to deal with). He has a younger man working with him, and he said he'd never seen a car that old in such good condition. He has a T-bird (I think it's an 87), so he knows a good bit about the Fox bodies. So far, I've only changed the headlights and plugs. I changed the headlights because the low-beam headlights had a lot of condensation in them.

Spark plug wires?

Reply #12 – March 14, 2015, 11:47:24 AM

Well I'm sorry to hear about your mom, I can relate...

Now on a 16K mi car that's been garaged all it's life and money's a issue, I wouldn't change/touch anything other maybe the coolant that will damage the radiator and/or the heater core if it gotten acidic... Oil changed 400-500 miles ago is fine... Fuel filter should not be a issue, will cause a bogging condition if it's restricted... Yes it's a maintenance item and should replaced once in awhile... AFAIK my two Grand Marquis 8 and 17 years old both have their orig(neither have yet turned 70K mi) as well as F150 that's is almost 20 years old & has 184K mi(orig owner never changed oil, serviced trans etc, why would they change a fuel filter? No, I've never even looked at it)... Plug wires can be checked for corona as mentioned, resistance of each can be checked with a ohm meter...

The plugs were likely bad due to short trips that never burned off carbon, eventually they'll foul(dealer should have addressed this issue)...

Spark plug wires?

Reply #13 – March 14, 2015, 10:42:31 PM

Thanks Turbo. I'm glad someone can relate.

The dealership didn't know about the coolant. I want to replace it to be sure. Tonight, I went out and started the Cougar, checking to see if any blue spark could be seen, and thankfully, nothing to report. It was pitch dark. Earlier today, I went to Advance Auto Parts to see if they could get the Motorcraft spark plug wires to fit the Cougar. They looked it up in their system and found they were discontinued. A dude behind the counter looked it up on his phone and said I could get them from Amazon. I'd really like to get them locally if I can. I checked AutoZone, and they didn't even carry Motorcraft. May check O'Reilly and Napa. Barring that, I may have to get them from Amazon.

Spark plug wires?

Reply #14 – March 15, 2015, 01:15:43 AM

Look them up for the same year mustang or hit a place like late model restro.

The spark plug wires are all the same, and most include muktipul length coil wires for the different engine bay configurations and are a generic fit.

Personally, i cut a spark plug wire while i was clearancing my alt bracket for my 3g upgrade (i was watching the gas line, didn't notice how close the grinder got to the wire) and replaced them with a set of $17 wires, which was the only thing in stock. Have had no issues, but ill have to see how long they last.