That power loss issue I've been dealing with really feels like my motor's breaking up at around 4,500 rpms or so.I replaced my plug wires recently, and made sure they were all tight on there, but I'm wondering if maybe the ignition coil could have a loose connection somewhere, whether it's the wiring harness on it or the plug wire on it? The ignition coil is a street fire with about 3k miles on it. The distributor has about 500 miles on it, and was brand new, not remanned. The plugs aren't that new, but I've pulled them all before and they all look to be in good shape. Any ideas on things to check? I'm having a local shop owner check the car over in a couple days to see if he notices anything.
>4,500 rpm problem.
- Thread starter 302GTS
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LethalInjection
Founding Member
If you haven't tried since the problem began, try cleaning your mass airflow sensor. Mine was sputtering and junk recently and cleaning it cleared everything up.
And if you haven't, pull codes.
I would want to swap plugs if you don't know about yours. How bad was the gap erosion? Be sure that you're not running platinum plugs.
If you have a spare coil, try it out. Plat plugs and a coil that is on the outs can both cause a break-up around 4K or so.
I would want to swap plugs if you don't know about yours. How bad was the gap erosion? Be sure that you're not running platinum plugs.
If you have a spare coil, try it out. Plat plugs and a coil that is on the outs can both cause a break-up around 4K or so.
Lethal, cleaning the MAF was the first thing I tried, and didn't fix the issue. By the way, the problem occurs maybe once every 2 or 3 times I go WOT, if that helps anything. And Hissin, I BELIEVE when I pulled the plugs last time they were Bosch platinums... I'll pick up a set of plugs this week and do that sometime soon to try out. I also have a new fuel filter to be put in within the next couple of days. Unfortunately I just threw out my stock ignition coil, so I can't try that out, but I'm sure I can borrow one off a friend. Do the SN95 5.0s use the same coil as the Foxes? I knew the dizzy was different, so I'm wondering if the coils are too.
95Cobra302
Founding Member
The coils are exactly the same and use the same part number. What's the deal with platinum plugs?? I've been running them for 9 years since I bought my cobra and haven't had any issues.
With some cars, especially if the ignition is a bit aged or there are mods to the car, plats can cause a low idle and a misfire around 4K RPM. Plat doesn't conduct as well as copper (i.e., Autolite 25's for E7 heads). When a higher RPM misfire pops up and plats are run, it's one of the first places I look. Since plats don't perform as well as copper (but last much longer - the lack of conductivity is made up for with low gap erosion), swapping in some coppers is something I don't hesitate to do.
There are more than a few folks that run plats without issue. You're lucky in that you're one of them.
There are also a lot of folks that had issues from running plats.
Jeff, as 95Cobra302 said, a fox III coil will work. So will a lot of the coils from other EEC-IV Fords. Since you had the issue with two different coils (from the sound of it), you probably don't need to worry about your coil.
Because the issue is intermittant and sporadic, I think some fresh copper plugs might do the trick for you. I'm really just guessing though bud. Also let us know what your plug gap was at. If much over stock spec and the plugs are plat, that could be it (you cannot really re-gap plat plugs, so you're stuck with them as they come out of the box).
Though stock is 0.052-0.056", I start my coppers between 0.045 and 0.050" to allow for some gap erosion (unless you check or swap plugs often, where you won't ever have much erosion).
There are more than a few folks that run plats without issue. You're lucky in that you're one of them.
There are also a lot of folks that had issues from running plats.Jeff, as 95Cobra302 said, a fox III coil will work. So will a lot of the coils from other EEC-IV Fords. Since you had the issue with two different coils (from the sound of it), you probably don't need to worry about your coil.
Because the issue is intermittant and sporadic, I think some fresh copper plugs might do the trick for you. I'm really just guessing though bud. Also let us know what your plug gap was at. If much over stock spec and the plugs are plat, that could be it (you cannot really re-gap plat plugs, so you're stuck with them as they come out of the box).
Though stock is 0.052-0.056", I start my coppers between 0.045 and 0.050" to allow for some gap erosion (unless you check or swap plugs often, where you won't ever have much erosion).
Got it, and I understand this is just a suggestion, but that's exactly what I'm looking for. I'll swap out plugs and fuel filter later this week and hopefully that'll solve the issue!With some cars, especially if the ignition is a bit aged or there are mods to the car, plats can cause a low idle and a misfire around 4K RPM. Plat doesn't conduct as well as copper (i.e., Autolite 25's for E7 heads). When a higher RPM misfire pops up and plats are run, it's one of the first places I look. Since plats don't perform as well as copper (but last much longer - the lack of conductivity is made up for with low gap erosion), swapping in some coppers is something I don't hesitate to do.
There are more than a few folks that run plats without issue. You're lucky in that you're one of them.
Jeff, as 95Cobra302 said, a fox III coil will work. So will a lot of the coils from other EEC-IV Fords. Since you had the issue with two different coils (from the sound of it), you probably don't need to worry about your coil.
Because the issue is intermittant and sporadic, I think some fresh copper plugs might do the trick for you. I'm really just guessing though bud. Also let us know what your plug gap was at. If much over stock spec and the plugs are plat, that could be it (you cannot really re-gap plat plugs, so you're stuck with them as they come out of the box).
Though stock is 0.052-0.056", I start my coppers between 0.045 and 0.050" to allow for some gap erosion (unless you check or swap plugs often, where you won't ever have much erosion).
I hate to go gravedigging for this thread, but I felt it would be good to allow others to see my issue and the solution. JT, the plugs were in fact the culprit. Swapped them out a couple days ago for a set of Autolite coppers, and the car runs like a dream!
This should just remind everyone to not jump to conclusions when an issue with your car pops up. Sometimes the simplest cleaning/tune-up can solve a mess of issues that occurs with your car. It's unfortunate that I spent money on a new air filter, fuel filter, and spent a decent amount of time making sure my TPS was set, cleaning the IAC, and cleaning the MAF, when the root of the problem was the set of spark plugs. Go for the cheapest easiest fix first!
This should just remind everyone to not jump to conclusions when an issue with your car pops up. Sometimes the simplest cleaning/tune-up can solve a mess of issues that occurs with your car. It's unfortunate that I spent money on a new air filter, fuel filter, and spent a decent amount of time making sure my TPS was set, cleaning the IAC, and cleaning the MAF, when the root of the problem was the set of spark plugs. Go for the cheapest easiest fix first!
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