<!--[if gte mso 9]><xml> <w:WordDocument> <w:View>Normal</w:View> <w:Zoom>0</w:Zoom> <w:PunctuationKerning/> <w:ValidateAgainstSchemas/> <w:SaveIfXMLInvalid>false</w:SaveIfXMLInvalid> <w:IgnoreMixedContent>false</w:IgnoreMixedContent> <w:AlwaysShowPlaceholderText>false</w:AlwaysShowPlaceholderText> <w:Compatibility> <w:BreakWrappedTables/> <w:SnapToGridInCell/> <w:WrapTextWithPunct/> <w:UseAsianBreakRules/> <wontGrowAutofit/> </w:Compatibility> <w:BrowserLevel>MicrosoftInternetExplorer4</w:BrowserLevel> </w:WordDocument> </xml><![endif]--><!--[if gte mso 9]><xml> <w:LatentStyles DefLockedState="false" LatentStyleCount="156"> </w:LatentStyles> </xml><![endif]--><!--[if gte mso 10]> <style> /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} </style> <![endif]--> On a 99’ 6.8L V10 Will a spark plug replacement be preventive maintenance to keep a blown spark plug from happening? What is a spark plug replacement running cost wise, better to go to a truck shop or a dealer? How hard is it to do your self, special tools required? Recommend stock plugs? Are the coil packs reusable? Come off easy?

Changed out the plugs on a LS1 chevy, it was all good except the one near the vacuum & break master was a royal pain.

I’m getting a click noise every now and then but it sounds like its coming from the AC compressor.

 

Do it yourself using factory Motorcraft Platinum plugs, anti-seize the threads when you install them and take your time. No special tools needed, coils can be re-used and come off easy. Just be sure to blow out the holes before you remove the plugs.

 

Make sure your engine is COLD when you do this.

 

Changing spark plugs is fairly easy. With the age of your truck I would replace both the spark plugs and boots. The boots are old if they were never replaced before and may not be in the best shape. For plugs use the direct replacement single platinum Motorcraft plugs.(single plat Autolites work well too) You can use an aftermarket boot which usually run about $4-$5 each and plugs around $2-$3 each. Rockauto is good source for parts if you prefer to get parts online. In my experience you get about 50k miles of quality running out of a set of plugs, Fords 100k interval is off.


I remove the intake tube between the air box and throttle body. One screw has to be removed then you can pull the whole coil and boot assembly out. If your carefull you don't have to unplug the connector to the coil. You will want to blow out the plug holes with compressed air before removing the plugs. I have a magnetic swivel spark plug socket set especially for the 4.6l, 5.4l and 6.8l 2V modulars from KD Tools (Part#: 41740) and it makes the job easier. Its a good idea to periodically check to make sure the plugs are tight to prevent a plug blowout.

The job is not that bad it can just be time consuming the first time you do it. The dealer will probably want over $250 to just change plugs (with no new boots) which is too much.

 

I also like to replace plugs every 50K miles for optimal mpg AND to reduce risk of them fusing since I prefer to not use anti-sieze.
The key to avoiding plug blow out is to NEVER under or overtorque plugs. These are steel plugs in an aluminum head.

In my opinion, a torque wrench is an absolute necessity and is the only tool that could be considered "special".

 

This----100%! While the controversy boils over on what the optimal torque is being able to consistently acheive the desired force is highly important. In fact I have one Wright USA made 3/8" torque wrench calibrated for inch/pounds and Newton/meters used only for these plugs. Anti-seize is another topic with big opinions but for me so far there has been nothing definitive citing it causes blown out plugs.

There is a wealth of information on just this site and some very interesting bits on blownsparkplug.com too. I'll increase torque from max of 14 ft/lbs to 21 along with using nickel-based anti-seize---this should serve me well or at least I hope it does!

Adding I remove my seats because this alone makes it much much easier for the gymnastics and contortions this task requires. I hear a nice warm day and couple beers also helps!

 

Good luck with getting an accurate torque reading with dry threads, antiseize or motor oil. Certain lubricants like from ARP are designed to get repeatable torque readings however it may not be the best thing for on spark plug threads.

 

I changed my plugs in our 2000 at 65K, I used Autolite (same as Motocraft) standard plugs and torqued them to 14 ft lbs dry. Rechecked them about 20K later and they where still tight. We will have about 110K on the truck when we get back to our homebase in Nebraska and I plan on replacing the boots and check the plugs again. I plan on changeing them at around 165K if I still have the truck.

Denny

 

Posted this elsewhere by mistake, reposting it here as it makes more sense.

I currently have a 2001 f-250 4x4 with the V10. I have a miss but not to sure how to find it on my own. Most of the coils are new and the rest are factory originals (I bought the truck new in 01, that's how I know). Over the years I've forgotten which are which, i'd hate to spring for 10 new coils when one or two could be bad.

If you were to check the ohms on each igintion coil on a V10 engine they should all read the same, correct? If one or more should read differently then the others then those would be bad, correct?

 

You can get the codes read and it should tell you which one.

 

My 12/99 v10 f250 has an ever so often intermittent miss I'm sure is a coil. Bout half of mine have been replaced. Friend of mine got me a set of accel coils for about cost so switching them all out.

After reading, I'm terrified to even try changing my plugs........... not knowing what has been previously done.

 

Blark: As the replies stated in your other thread static ohm readings are NOT effective apart from assessing a gross failure of a COP. Without aid of even the most basic of scanner/code reader its difficult to easily determine which plug or coil OR connector/wire harness might be bad. I’d suggest this to you: with engine running disconnect each COP while carefully observing if there is any change. Right now you have a miss or two which is noticeable so use that as your baseline. As you remove each COP from the circuit anything causing another change in the engine smoothness is a good COP, any disconnected COP that does NOT change performance is a bad COP or perhaps loose connection at the COP or a possible cut/damaged wire in the harness. Chances are you simply have a bad COP which can be determined as I describe.

DirtRocker: An intermittent miss tends to not be a failed COP but is possibly a bad connection or other problem. COP’s don’t seem to misfire although its not impossible, just not too common---they’re either good or bad. Could be the plugs or many many other things as well. Again the scanner/code reader is an invaluable bit of gear for these Ford modular motors, even the most basic of them work well but one with code canceling capability is best.

Changing your own plugs doesn’t need to be as scary as it might seem but it does require just a bit of care and knowledge before you begin. These forums are filled with great ideas, suggestions and real life experiences that can prove to be as helpful as any other information you’ll likely to find. The best advise is to read as much as you can here, ask questions, make notes then block out a few hours and jump in. After that first time all this makes perfect sense and you’ll have your own bits of info to share.

Best of luck to both you guys!

 

Wow, before we moved up here I bought a set of Champion platinum plugs for the truck.

Had it at the shop today (no effin' start - another fuel pump?) and asked the mechanics if they'd install the plugs while under the hood.

They were pretty adamant about only using Motorcraft plugs. Said they made lots of money replacing other types. I told them to hold off on the plugs.

What's the skinny on "aftermarket" plugs and these engines?

 

I think it has something to do with design, but don't know for a fact.

All I do know is that my F150 HATED Bosch spark plugs. It didn't run or idle as smoothly. Replaced them with Autolite/Motorcrafts, truck purred like a kitten.

 

I can't speak about the design or operating characteristics of the MC plugs but in general one has to think the company building the engine should have the best plug for optimum performance, fuel economy etc etc.

I've read somewhere and cannot find the thread again that mentions MC plug threads are cut a bit differently than a long ago "standard" thread used by most every USA engine manufacturer. It was easier swapping plug brands and often times did in fact provide better performance. I gues it makes sense now to use the MC plugs not only for the more compatible thread configurations but time and time again we see someone whose switched brands only to suffer with a loss of something in these modular motors.

Sure the newest, latest & greatest thing might be attractive but in the end seems MotorCraft wins every time!