I recently had a rough running engine and check engine light. The folks that sold me the truck replaced a coil. 140 miles later, I'm experiencing the same symptons. I've just dropped off the truck so I don't know yet if it is the same problem or not. Assuming it is, is this a common problem with these? If so, any suggestions on improving the system other than just replacing the coils as they go bad? Truck is a '97 with 87K+ and 5.4 L V8.

 

Welcome to the forum

You have 8 of them, if one failed, it is likely that others will follow.

 

I had the same problem a few months ago with my '99 5.4 F-150. It happened on a Sunday, so options were limited. I went to local Pep Boys, they replaced the bad one (I could tell them which it was because my SuperChip Tuner reads codes, but they did the diagnostic ($100) to be sure. I think I ended up spendingalmost $300 for the one coil. Monday morning, I had another take a dump, so I took it back, and had the other 7 replaced. Got a nice discount on labor, and got out the door for ~ $500. No problems since!!

 

Yep, common problem - if you search the forum for "COPs" you'll see a bunch of posts. I don't think you can do much except replace the bad ones. Consensus seems pretty strong that buying fancy ones doesn't improve HP or MPG. They just cost more. Lots of posts suggest staying with Motorcraft, but I put Accels in mine about 5k ago. No problems, work fine and cured my missing.

I didn't think it was very hard to do, just the #7 - maybe #6 - where the fuel line has a regualtor or something right over the COP bolt. I didn't have a thin enough rachet so I squeaked it out 1/32 of a turn at a time - took about 30 minutes for that one bolt. Next day I bought a ratchet and had it done in no time. Pop always said use the right tool for the job, but sometimes you just gotta do what you gotta do.

 

your better off replacing all of them. i have a 99 5.4 and had the shop replace 2 of them at 210 a shot, i finally went to advance auto each time the cel light came on and had them read the code and pay 41 bucks a piece for a cop instead of fords price of about 110. dont forget the dielectric grease

 

Troyer Performance has a good replacement set if you want more performance. The coils are hotter than stock & come with plugs to match the extra fire the coils have.

 

what does "cop" stand for? I have prices ranging from $36-$67 for after market replacement coils. don't know what the difference is. is there a diagnostic tool I can buy which will tell me which plug is out?

 

Coil On Plug. OBDII will set a DTC for a misfiring spark plug and will turn on the CEL. Any OBDII code reading tool will read DTCs. Most people that don't have an code reader will visit Autozone where they will check the DTCs for free.

 

I had to replace 3 coils on the 01 4.6l that I owned. I never once got the check engine light to come on. it would just randomly start dropping a cylinder every once in a while.

The service dept I took it to tried to say it was just the boot between the coil and the plug. I wasn't buying it but hey lets give it a shot. I wasn't a mile away before I made a U-turn and headed back in. The nice thing about it was the 40 they charged me to replace the boot got applied to the $50 deductible of the extended warranty. They considered it an on going problem.

They didn't jack with saying it was a boot the second and third time.

 

I'm heading down to the parts store for the same problem, and from the sounds of it, I should buy all 8 to avoid more failures.

Diagnostic tools, aka Scan Tools or OBDII scanners are a diagnostic tool that will read Data Trouble Codes (DTC's) from all vehicles 1996 and newer. They range in price from around $60 to well over $200 for basic functions. The low end models will only read the code and will not clear the Check Engine Light (CEL). The code definitions can be found on this site or in your manual.

I just bought a Scan Tool for about $200 that will read the codes, provide the definitions, clear the CEL, perform live data monitoring while driving and can be set up to take 20 frame snapshots of the various monitoring systems, which can be triggered manually or by an incoming DTC. It has been worth every penny so far and I've only had it a about a week.

I wanted one because I have four vehicles and I don't like taking it somewhere else to find out why the CEL came on. I hope in the future, the manufacturers will start adding it as an on-vehicle option.

 

$210 per coil? that's the highest I've seen anybody claim. At the Ford dealer they're $98 per coil for oem motorcraft. You got shafted on that one. If you watch Ebay quite often there will be someone selling a lot of 8 OEM Motorcraft coils for reasonably cheap, even cheaper than the auto part store brands! I found all 8 several months ago for $175 and replaced them all in about 2 hours. Once your coils start going bad, they seem to drop off like flies.

 

GM is the only manufacturer I know of that has on-board diagnostics so far, but Ford likes to keep things hush-hush when it comes to working on your own vehicles anymore. I've got a Snap-On microSCAN ($875), and I can't read anything more with it than the cheaper ones on Ford, but I can do alot of the functions that the scan tools can do on GM and Dodge.

 

I just ordered 4 coils/boots from ebay, new with a 3 month warranty for 10.50 each, following a link from another thread about COPs. I hope that's not "too good to be true" but thought I'd take the chance.

 

The 3 month warranty won't get you anywhere, and "cheaper" never equals "better" so I'll guess we'll see how far down the road they get you. They're able to sell you those coils cheaper because very very cheap parts are used to build them. Remember, even though they're selling them for "10.50", they're still making a huge profit on them, so no telling how much they're paying for them. The Motorcraft coils last for 200k+ miles and are made to put out the power and withstand the heat that your modular motor needs to operate properly.

 

If you look harder through Ebay, there are ones that have a lifetime warranty. Over on F150.net there are a lot of guys running them with no problems.

How many places actually make these coils? I bet it's one or two and they just put different labels on them. I'm sure that there isn't a Motorcraft COP factory, an Accel, an MSD, an el-cheapo, a Grannetelli or however you spell it.

Mike