lmarlo

I posted awhile back about my 07 GT with 67k miles starting to misfire on moderate acceleration. Y'all gave me a bunch of things to try. Here's the rundown: No check engine light. Cleaned the MAF. Cleaned the throttle body. Reset the computer. Ran Techron thru. Ran Seafoam thru. Ran a tank of 91 octane thru with about 80 miles of it or so on the freeway. Had an expert (rave reviews on Yelp) ride with me with his scanner - No codes. His opinion - definitely a misfire. He was nice enough not to charge me. However, he suggested a spark plug change, and wanted $400. I'm retired and on a budget, so I passed, for now. I thought I'd try replacing coil packs before doing plugs. I know everyone said only OEMs, but the price was crazy. I found some with the DG511 part number for $90 (all 8). They fit a bunch of Ford SUVs, Ford trucks, a Lincoln and 05-08 Mustang GTs. I installed them myself. It was fun. Took her out for a spin. No misfiring. Runs like new. Here's where it gets crazy. Very next morning, I start to roll out gently, and she acted as if the clutch was slipping for only a few feet, or as if it was missing badly. That's the best way to describe it. After it gets rolling, it runs beautifully. Will not do it if I take off quickly. I do let it run till it idles at 1000 before I take off. Didn't do it again until the next morning. I start it later in the day multiple times and it doesn't do it. It does it every morning. BTW, I'm easy on the car. It's never been power shifted. Yes, I jump on it every now and then and do speed shift it. What could be going on? Do I have a bad coincidence with something else happening? Thanks, Lenny

Derf00

(8) DG511 for only $90? Can you post the link?

Were they used? If not, they're counterfeit. Amazon and E-bay have both been found to have counterfeit parts for sale on their sites. They don't do this on purpose but they also cannot vet every vendor that sells through them. You just have to be careful when purchasing on-line.

I'm curious why you went through the trouble of replacing the coils, but not the plugs? It's the plugs that are generally a wear item, not the coils.

lmarlo

The web site is 1aauto.com. I actually paid $89.90 for all eight (free shipping). They are brand new - the top of them is beautifully shiny and the contacts were new as well when I applied the dielectric grease. I did the coils first because of money primarily. And the coils, as I have read here, tend to go bad as well. Lastly, I put them in myself, saving more money. She now runs great as I said.

bl817

IMHO, your going to hate yourself later if you don't get those plugs out asap. at least to check them out, clean them off and apply some nickel anti-seize to the snouts only. my $.02. good luck

lmarlo

You're right, of course. The plugs are in my plans - I actually bought them before the coils, but did the coils first, which did solve my problem. I mean she was a bucking bronco on accelerating at low speed in 5th. Now she is smooth, so the coils worked.

flash_xx

Against all forum suggestions I decided to replace my coils with MSD. The OEM's were fine as far as I could tell but I decided to replace them anyway. So far they've been working great. Almost two years now. Did it gain any performance? Not that I could tell, but then again I haven't retuned the car.

As far as sparkplugs go I still use the oem autolites, I just check them from time to time an put some nickel grease to keep them from sticking. Tried the champions and they went bad quickly.

Derf00

Ok, yeah, I'm familiar with that site. You have to read their descriptions carefully. What you got were DG511 equivalents which are the 1aauto brand. I have no idea who makes their parts nor do I know the quality of their own branded parts. The genuine Motorcraft DG511 are running $409.95 for 8 or $62.95 each on their site. Each coil would also have come in a Ford Motorcraft box. IF the coils you got came in a Ford Motorcraft box, that would be Fraud and I would demand my money back.

The long and short of it is, do the spark plugs and if the problem persists, I'd contact 1AAauto for exchanges. $10 per ignition coil = cheap construction IMO.

As for plug brand. I'm on my second set of champions and have had zero problems on either set. Problems with the champs (from what I've read) are cracked porcelain or misgaped plugs. The cracking is due to being dropped most likely and the misgaping, well that's on the installer for not checking it before installing. Besides, if the gap is way off (small), it's probably a sign the plug was dropped at one point.

lmarlo

So what if I have DG511 equivalents that work? What's wrong with that? I'm not going to pay $400 plus if can pay $90. You've had good luck with champions. Yet I found people on this site that say they are crap. So I bought the OEM plugs, because fewer people said they were no good. Apparently, everyone seems to be an expert, yet not one person responded with an answer to my original question. Instead you all changed the subject and started harping about coils and plugs. Pissed poor communication skills.

Derf00

I'm correcting you because you make it seem like you bought Motorcraft DG511 for that price, not an equivalent. They are not the same thing anymore than saying a Cadillac STS is a Chevy cobalt, they're both GM and they both get you from point A to B but they are way different.

What have we not answered?

We've stated the plugs should be changed due to mileage. 100K miles before changing the plugs is a sales pitch, not a reality. The reality is right around the mileage you are at. Bad plugs could create a miss or sluggish performance. You've reviewed the forums so you know that the two piece ford plugs break in most cases yet only a couple of instances where a Champion plug failed in a similar way. Most Champion plug failures are due to user error, not the product. I'm guessing you haven't pulled the old plugs out yet?

Good luck, and I mean that sincerely. Follow the TSB and ford recommended methods to remove them without breaking them. Keep in mind you'll be reinstalling the same type of plug with the motorcraft plugs. That's what I didn't like and why I went with Champion.

With regard to the coils, you get what you pay for. $10 each coil is not going to be anywhere near the quality of an OEM coil or even a top tier aftermarket brand and can quite possibly fail in a short amount of time thus making you think , It can't be the coils, I just bought new ones.

Inferior/cheap coils are not typically held to the same quality standards of the OEMs or top tier brands. Cheap, inferior coils may have a wider voltage difference coil to coil, the insulating materials they use may not be up to the same level thus they fail sooner (Work great for a bit but then crack or have internal voltage leaks). Again, you overlook the coils because you just bought them.

You will find that the majority of people who have tried aftermarket coils on Fords find that they don't last as long or reliably. Definitely do the plugs but if that doesn't resolve the issue, i'm going to tell you to check those coils again.

To better educate yourself here's a couple links below. I'm not saying that condescendingly but you asked for expert info.

General information about coil construction, coil testing, coil failure and the types of testing companies do and how to spot sub-par coils.
http://www.autoserviceprofessional.c...to-know?Page=7

More info includes better details about how coils fail (starting on page 15) http://beru.federalmogul.com/sites/d...3_lowres_0.pdf

bl817

I'm saying it condescendingly, OP, you asked for info and got just that. now all your doing is trying to justify not buying OEM coil packs and that's fine, its your car. there is a lot of arguing and non agreement on a lot of things on this site but not once ever have I read anyone giving bad info to try and help someone that is truly wanting help. so go drive with your $100 coils and don't change your plugs. we will be here to help when one or both need changed. get the Lisle 65600 tool, my $.02. good luck