coil pack failure rate?

[ohioshodude]

hey guys. nothin like a sho to **** you off right? lol ok here is the story. After taking the 97 in for a studdering problem it was told to us that it was a REAR coil, we had it fixed and it ran find for a week. now its doing it again, we took it back yesterday and they told us it was another one again in the rear. is this going to be a weeky thing with the coil packs?! or is this a fluke? i've never herd of a gen III have more then a coil go bad at a time. this is getting $$$$$$ :cry: :cry:

 

[AutoSHO]

From what I understand they all fail, its just a matter of time - Some have also had success rotating the coils, swapping the front 4 to the back, and vice versa.

 

[nothingtoseehere]

Did they replace all the rear coils or just one? If a coil goes bad, you are suppose to replace them in groups of four, or eight if you can afford it. Essentially, replace all the rear at the same time or all the front or all coils.

 

[MilTownSHO]

Did they replace all the rear coils or just one? If a coil goes bad, you are suppose to replace them in groups of four, or eight if you can afford it. Essentially, replace all the rear at the same time or all the front or all coils.

Sounds like just one was replaced, if one goes out agian, just have them all replaced on that bank if you can afford it.

Our 98 with 40k I think is having a coil go out slowly myself, it's a common problem, I didn't have them swapped during the cam weld though since it only had 32k on it when done.

 

[ohioshodude]

well thanks guys, i didn't know this was a common problem. maybe i'll tell my dad to just save the money for the coils and i'll replace them myself. i've been trying to talk him into working on it, he just doesn't want to mess anything up. i on the other hand have no fear, many intake removals, among other things on v6's this can't be too much more complicated. why is this so common? does the heat get to them? i thought coil packs were pretty stout unit that could take tons of miles.

 

[ArkanSHO]

i on the other hand have no fear, many intake removals, among other things on v6's this can't be too much more complicated. why is this so common? does the heat get to them? i thought coil packs were pretty stout unit that could take tons of miles.

I never removed an intake from an early GEN but I can tell you that the first time I took mine off it was a 2 hour ordeal since I had no idea the tray under the passenger side of the windshield came off with three screws after popping the grille above it off. The brackets that hold the expansion chamber from the back are a PIA to get to otherwise. Kirk has figured out a way and I saw him do it but I couldn't explain it but it took him like 40 minutes to expose the cams in the rear.
The heat is pretty much the culprit in the case of the rear coils failing. There is little air flow back there and a chunk of foam rubber that Ford stuck to the length on the bottom of the intake for vibration doesn't help any either. Once the intakes expansion chamber is out of the way (two mounting brackets in the rear, the EGR valve, a couple of small bolts for the cooling line bracket, the SAI valves on the backside which conveniently block one of the mounting bracket bolts, brake booster vacuum hose, throttle body elbow and 16 hose clamps or 18 upper intake bolts) the coils are a piece of cake to replace.

 

[stephen newberg]

I am at 122k with the original coils still doing fine. I did swap back to front when I had the cam sprokets welded a year or so ago.

pax,smn

 

[ohioshodude]

hey guys,

some new info. removing the intake was much easier then i thought. similar to the v6 maybe a little harder. we replaced all the rear coils and still its missing at under 2k rpm. i haven't a clue whats wrong now. only thing i can think of is that its one of the front ones now. it does feel like it gain 5-10 hp, it almost spins the tires now, hehe damn gen III's no tire noise. i'll try switching coils on it see what that does. any other idea why its missing from idle to 1500-2000 rpm?

 

[ohioshodude]

alright got a new one for you. turns out the misfiring and studdering is due to the MAF. joy. hehe i figured i'd unplug it and see what happens and damn it if it didn't run like it was supose to. and today it was so bad the car wouldn't run for more then 2 mins. so if anyone has this missfiring issues i suggest unpluging the MAF. it's always worth a try. now i just have to find a v8 MAF. anyone have one? acutally i found out the 3.4l MAF is the same as many many fords. most with the 4.6l so i'm sure i can find one. so a hunting i shall go..

 

[JSIL1]

How does one go about killing the coils prematurely, if at all possible?

 

[MilTownSHO]

it almost spins the tires now, hehe damn gen III's no tire noise.

Unhook the battery and let the car completey drain off all memory. Hook the battery back up and romp on it, let the computer relearn the driver. It will spin the tires.

 

[MilTownSHO]

How does one go about killing the coils prematurely, if at all possible?

I don't think there is a way to **** them quicker

 

[UnsungZero]

I don't think there is a way to **** them quicker

well you could throw the coil packs into the microwave and ....well you know the rest

 

[ohioshodude]

help

Well we went to the junkyard today and got a new MAF of a continental, and guess what. it still runs like ***. anyone know what could be causing a misfire so bad that it will stall the car. We are going to check the fuel pressure next. See if that can tell us anything. Help, please, before my dad sells the sho! He’s not as patient as me with sho's.

 

[SHOZ123]

A vacuum leak will cause missing and stalling. I would suspect this with the intake being recently removed.

 

[ohioshodude]

thanks paul i didn't consider this. i'll check it out, lets hope this is the problem. thanks

well i checked the intake and everything seems ok and is plugged in. the EGR vacum seems low but its not supose to be open all the time either, so that might be nothing..

i'm thinking maybe the IAC is to blame. it runs horrible at idle, and if left at ilde for a few mins will just shut off. no change in engine noise, just stops running. if i unplug the IAC while the engine is running i get the same type of shutdown. we checked the fuel pressure and everything there is within spec. also played coil switcherroo on the front and that made no difference. so i am really stumpped. unless one of the new motorcraft coils in bad in the rear i'm out of ideas. i wish i knew a place that would read codes, i guess i'm gona have to buy me one.

 

[SHOZ123]

Check for a vacuum leak with some spray carb cleaner. With the engine hot and running spry the cleaner on any suspected joints or connections. The idle will change if there is a leak found.

 

[Tim Rice]

IAC's get real dirty

pull the IAC off and I'll bet there is a gang of carbon built up on the pentle and in the manifold, almost all the ford engines 4.0,3.8 ect experience this problem. When I worked at the Ford dealer here in town the Tech's would throw a new IAC motor at them and untill you throughly clean the #$*@ out of the port it will continue

Good point about the coils, I am going to check all of mine before installing the spare engine (wonder what the resistance should be?), Let me know if you need a spare, I have 16 total, I'll send ya one