Looking for recommendation for first time replacement of spark plugs and plug wires for my '06 Mountaineer. Prefer not to pay dealer $$$. And, is this a difficult job?
Also: Anyone know of a Mercury-specific forum of any worth (other than FTE Thanks!

 

IIRR you have COPS (coil on plug), no spark plug wires
For spark plugs, Motorcraft, if you by chance have sp wires, I would recommend Ford Racing through summit......they are very good quality wires, much less than oem direct replacement.

 

My 2004 Mountaineer with the 4.6L had CoP, so I would bet the 2006 does as well. It's about a 30 minute job to change all 8 spark plugs out, hood up to hood down, if you have the tools (standard 5/8" spark plug socket, 10mm socket, extension, extendable magnet, ratchet wrench).

I've used Iridium plugs in most of my vehicles since 2002 model year and never had an issue, but others will suggest OEM only plugs.

-Rod

 

Thanks for the response, Folks. This truck new to me... didn't realize I had CoP.
Have 95k miles and am sure nothing much has been done to this truck. Am shooting for better mileage
Guess I have to ask the expected lifetime of these units?

 

If you're sure not much else has been done to this truck, I'd suggest you consider having the transmission fluid and filter changed out soon as well. I wouldn't necessarily go for a transmission fluid flush, just stick with the fluid drain, filter replaced, and refill. That would also be a good time to change the differential oil and transfer case oil.

The brake fluid is often neglected, as is the coolant, so if you are serious about making this truck last, consider flushing those systems.

As for getting better mileage, use synthetic or synthetic blend engine oil of the correct viscosity, make sure the air filter is clean, clean the Mass Air Flow (MAF) sensor, keep the tires inflated to the pressure listed on the door sticker, and be easy on the throttle. Even will all that you're probably looking at around 15 mpg in city and 18 mpg on the highway. Performing a cylinder decarb may not help with fuel economy, but it will likely help with responsiveness and power for when you need it. A can of SeaFoam is around $9 typically and you'll use 1/3 to 1/2 a can for a decarb, so it's money well spent.

-Rod

 

I would also say that yours should have the COP, so no wires to replace. I know a lot of people have mixed opinions on COP setups. Some argue that COPs fail and there are more that could fail. Most COP failures in my opinion, are due to the spark plugs not being changed, which causes the gap to increase, which increases the stress on the coil. It has to build up a stronger charge to jump the gap, and that causes electricity to try to find alternate paths, and sometimes that means breaking down the insulating resin inside the coil and forming a short.

If it were mine, at the very least I would inspect and regap the plugs every 50,000 miles to make sure they stay within spec and don't build up any harmful deposits. I would do this regardless of the plug type. As far as what plugs to use, you usually can''t go wrong with Motorcraft brand. Just make sure that they give you a double platinum or better plug. If you go with an aftermarket brand, use either Autolite or NGK. These are proven to both be excellent well made choices. Stay away from Bosch, there are many people who have had bad experiences with them, myself included. If you want, you can run an iridium plug. The benefits of doing so include: longer plug life, less gap erosion, cooler plug tip, less tendency to foul, and stronger more focused spark. This could yield a slight increase in economy, but mostly it just helps with keeping the ignition system within spec.

I agree with changing all the fluids listed above.

 

Again, thanks for the input.
One last thing I you may know... My tranny seems not to be able to decide which gear to stay in running up a hill at constant throttle.
I'm aware that a dedicated transmission code scanner can test all solenoids even without the engine running. I'd like to see those codes.
Do auto supply shop who do systems scans for free typically have a dedicated transmission scanner?

 

I've not seen anything other than standard consumer-grade scan tools at the local parts houses. Generally to find ones that will access more than powertrain (P-code) codes you'll need to visit a professional shop, dealership, or find a hardcore DIY-er that likes gadgets.

-Rod

 

Not staying in gear could be a number of things, like you are down on power, or your hill is just too steep. Even though you are at constant throttle, the computer is constantly calculating engine load, and it may decide that based on the amount of load you have that staying int he higher gear is not a good idea, so it downshifts, which decreases the load, and the computer decides that it might be good to upshift again. Best thing to do in said situation is to hit that magical OD off button (read the owners manual for details). This forces the trans to stay in the lower gear which reduces wear and tear on the transmission, reduces heat, and cuts down on unneeded shifts. It also makes the engine run a little cooler.

What maintenance have you done on your transmission? You need to change the fluid every 30,000 miles with the proper spec fluid, and doing a filter change at the same time is a good idea. If you have not had a fluid change in the last 30,000 miles, now would be a good time, especially if you are driving up hills.

 

Thanks Mr. Guru, Sir
I am sure the previous owner has done none of the scheduled maintenance other than oil changes, so a fluid change is likely in order. The hills I'm climbing are not very steep, nor is my load more than the normal gross weight (except for that cheeseburger at lunch) so there's no abnormal stress, just an over-sensitivity to shift.
I'll do the fluid and filter, but seek a code readout soon, to be sure.
Thanks!