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It's possible; the wires that are shielded on my car are the cam sensor and crank sensor; probably on yours too.

Both of those signals are sensitive to edges, or transitions in the signal, not a voltage level; so this is a good place to look.

They care about When it changes, not What it is or changes to. (A TPS wants and tracks a voltage; the crank sensor wants to know when the timing mark passes.)

These voltages are from magnetic reluctance sensors, so they are tiny.(https://en.wikipedia.org/wiki/Variable_reluctance_sensor)
This is a fancy name for a coil of wire, wound around a pole piece; some of the pole pieces are magnetic, some are not, and if that's not correct it won't work. I think they all have magnets now.

To check the circuitry wiring, the best way is to untape them and separate them as far as you can from each other, and everything else. Then see what happens.
You can then wiggle individual wires, and see what effect it has.

You can replace those with Coax cables, but it needs to be rugged stuff to handle the heat. And it's a pain.

Covering them with aluminum foil with a bare (ground) wire to a bolt on the chassis should reshield them as good as you can for troubleshooting purposes.
Just wrap the foil around the wire, with a piece of bare wire crumpled inside; that will work for a few days without solder or whatnot.
It will eventually corrode where the copper hits the foil and lose the grounding effect, so then you rip it out and do it again with fresh foil/wire.

I use some of this stuff, that I rescued from a dumpster after it was removed from a project: https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=7902
Aluminum foil works just as good, but it's hard to solder to. :)

Another thing I do to sensitive electronics, is take a large heavy AC drill or side grinder that sparks a bunch, and hold it nearby, hitting the trigger, and see if it screws up when you hit the trigger; nothing causes interference than an old 15A drill sparking next to it. :)

Doing that may give you an easy check, and after you separate the wires, pinpoint where the problem is.

A handheld 'taser-like' device works well too. :)

If the ignition triggers in time to the interference, it's a pickup problem for sure.

You might also try the AM radio check.
Find an old AM battery powered radio, tune it to a blank spot, and with the car running, wave it around and see where you pick up noise. If you hear the ignition coming thru, you have a spark leak Somewhere; it will get louder the closer you are to the source.
(I use this a lot on electronic interference problems; some of my preamp prototypes have shut down all the cell phones in an area before.)

If you hear other noises, suspect the grounds; that means a fast moving signal is taking a longer path back to ground than it should.
Sticking the antenna inside the loop formed by the signal from source to ground makes that one louder.
 

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Discussion Starter #342
It's possible; the wires that are shielded on my car are the cam sensor and crank sensor; probably on yours too.

Both of those signals are sensitive to edges, or transitions in the signal, not a voltage level; so this is a good place to look.

They care about When it changes, not What it is or changes to. (A TPS wants and tracks a voltage; the crank sensor wants to know when the timing mark passes.)

These voltages are from magnetic reluctance sensors, so they are tiny.(https://en.wikipedia.org/wiki/Variable_reluctance_sensor)
This is a fancy name for a coil of wire, wound around a pole piece; some of the pole pieces are magnetic, some are not, and if that's not correct it won't work. I think they all have magnets now.

To check the circuitry wiring, the best way is to untape them and separate them as far as you can from each other, and everything else. Then see what happens.
You can then wiggle individual wires, and see what effect it has.

You can replace those with Coax cables, but it needs to be rugged stuff to handle the heat. And it's a pain.

Covering them with aluminum foil with a bare (ground) wire to a bolt on the chassis should reshield them as good as you can for troubleshooting purposes.
Just wrap the foil around the wire, with a piece of bare wire crumpled inside; that will work for a few days without solder or whatnot.
It will eventually corrode where the copper hits the foil and lose the grounding effect, so then you rip it out and do it again with fresh foil/wire.

I use some of this stuff, that I rescued from a dumpster after it was removed from a project: https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=7902
Aluminum foil works just as good, but it's hard to solder to. :)

Another thing I do to sensitive electronics, is take a large heavy AC drill or side grinder that sparks a bunch, and hold it nearby, hitting the trigger, and see if it screws up when you hit the trigger; nothing causes interference than an old 15A drill sparking next to it. :)

Doing that may give you an easy check, and after you separate the wires, pinpoint where the problem is.

A handheld 'taser-like' device works well too. :)

If the ignition triggers in time to the interference, it's a pickup problem for sure.

You might also try the AM radio check.
Find an old AM battery powered radio, tune it to a blank spot, and with the car running, wave it around and see where you pick up noise. If you hear the ignition coming thru, you have a spark leak Somewhere; it will get louder the closer you are to the source.
(I use this a lot on electronic interference problems; some of my preamp prototypes have shut down all the cell phones in an area before.)

If you hear other noises, suspect the grounds; that means a fast moving signal is taking a longer path back to ground than it should.
Sticking the antenna inside the loop formed by the signal from source to ground makes that one louder.
More digging does indicate that this is it. There is the concern of the aluminum shielding and then there is the concern of having any of it too close to the wiring for the alternator or the alternator itself.

I think I may be on to something because I also found this: https://forums.corral.net/forums/general-mustang-tech/2055161-tfi-harness-foil-shielding.html
 

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I'd see if the local lowes or homedepot has any 18awg Shielded wire; something with a nice heavy braid.

It has to be stranded, or it will break, but for garage troubleshooting, you could use TV coax cable. IIRC, you'd need two pieces of coax to replace 1 of the wires. (2 signal wires, +ground.)

It's important the entire wire is covered with shielding, and the shield is grounded good to the signal ground, as the stock one is.

I believe those are two signal wires, covered with the mylar/aluminum foil shield, which is connected to a third pin, which is ground at the eec.

The shielding touching ground somewhere else can cause problems too, so make sure it's not touching somewhere else.

Some shields are connected at one end only, some are both ends, I'd duplicate the factory setup.

I have a couple of rolls of wire that would be perfect for that, I thinks it's alarm wire, or maybe some kind of lighting wire. The heavy braided ground is the important part.

The factory shielding is fragile, so it's not hard to mess up without massive rewiring. :)

If you've got a stretch without shielding, I'd start there, that's a problem for sure.
 

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Discussion Starter #344
I'd see if the local lowes or homedepot has any 18awg Shielded wire; something with a nice heavy braid.

It has to be stranded, or it will break, but for garage troubleshooting, you could use TV coax cable. IIRC, you'd need two pieces of coax to replace 1 of the wires. (2 signal wires, +ground.)

It's important the entire wire is covered with shielding, and the shield is grounded good to the signal ground, as the stock one is.

I believe those are two signal wires, covered with the mylar/aluminum foil shield, which is connected to a third pin, which is ground at the eec.

The shielding touching ground somewhere else can cause problems too, so make sure it's not touching somewhere else.

Some shields are connected at one end only, some are both ends, I'd duplicate the factory setup.

I have a couple of rolls of wire that would be perfect for that, I thinks it's alarm wire, or maybe some kind of lighting wire. The heavy braided ground is the important part.

The factory shielding is fragile, so it's not hard to mess up without massive rewiring. :)

If you've got a stretch without shielding, I'd start there, that's a problem for sure.
I think the shielding is certainly something to check but one of the things I was just reading mentioned the wiring being too close to the alternator. I just checked and my wire bundle was sitting right behind the alternator. I have relocated it so that it doesn't come near the alternator.

Here's the thing; when I relocated all of it, IIRC, the cable bundle routed across the core support to the passenger side air box area. It basically went around the world. When I relocated it I took the most direct route and that it right up against the alternator.

It's too late to test tonight but I'll give it a shot when I get home from work tomorrow evening.
 

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I can see the alternator messing it up; especially if there's a loop of wire in the bundle. :)

The alt is a big magnet spinning around in an aluminum housing that won't shield the magnetism, so there a spinning signal generator right by your wires, probably making pulses of it's own, randomly related to the real timing signals.

Foil or braid wire shielding does nothing to magnetic fields; I've designed circuitry to go in an MR scanner, lol.

The easy check is to disconnect the alt wiring; that will take 30 seconds with a 8mm. :)
Stick a charger on the batt to be sure.

It should run for a while with no alt anyway, and if the problem goes away, that's the problem.

If you have a piece of 1/8" wall steel tubing to run the wires thru, that should shield it. :)
 

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Discussion Starter #346
I can see the alternator messing it up; especially if there's a loop of wire in the bundle. :)

The alt is a big magnet spinning around in an aluminum housing that won't shield the magnetism, so there a spinning signal generator right by your wires, probably making pulses of it's own, randomly related to the real timing signals.

Foil or braid wire shielding does nothing to magnetic fields; I've designed circuitry to go in an MR scanner, lol.

The easy check is to disconnect the alt wiring; that will take 30 seconds with a 8mm. :)
Stick a charger on the batt to be sure.

It should run for a while with no alt anyway, and if the problem goes away, that's the problem.

If you have a piece of 1/8" wall steel tubing to run the wires thru, that should shield it. :)
Well, like I said, I just moved the wire so that it takes a different route to get to the distributor where it doesn't pass by the alternator at all.
 

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I'd never considered the alternator as a source of magnetic interference; I'd bet this is it, and I'd have probably never thought of it.

I won't forget now, tho. :)

The fields in the alternator are a lot stronger than the fields driving the sender.

That explains why ford spent money on extra wire. :)

Does the 5.0 have a crank and distributor trigger, or just the distributor? IDK why it would need both...

My only question now is: did it help? :)
 

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Discussion Starter #348
I'd never considered the alternator as a source of magnetic interference; I'd bet this is it, and I'd have probably never thought of it.

I won't forget now, tho. <img src="http://forums.tccoa.com/images/smilies/vb2_smile.gif" border="0" alt="" title="Smile" class="inlineimg" />

The fields in the alternator are a lot stronger than the fields driving the sender.

That explains why ford spent money on extra wire. <img src="http://forums.tccoa.com/images/smilies/vb2_smile.gif" border="0" alt="" title="Smile" class="inlineimg" />

Does the 5.0 have a crank and distributor trigger, or just the distributor? IDK why it would need both...

My only question now is: did it help? <img src="http://forums.tccoa.com/images/smilies/vb2_smile.gif" border="0" alt="" title="Smile" class="inlineimg" />
It's just a distributor.

I'll find out tonight.
 

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Discussion Starter #350
So, it must be a wiring issue. I took apart the "bundle" for the ignition control module to the distributor/coil and ECM. The foil is generally intact and it appears that Ford just put a bare ground wire in place and then wrapped it with foil tape. I had a part of it that was a bit messed up so I wrapped it in some aluminum tape that I have.

Looking through my schematics, it appears that the tachometer connection sits on the other end of a resistor where T/Y is converted to W/PK. I guess I need to track that all down and figure out the right way to wire in the tachometer.

I was incorrect about the wire routing across the front of the engine. What it did was route the power for the ignition (R/LG) across the core support to the PCM relay and a fuse in the fuse box under the hood. That's a constant power feed versus a switched power feed. I honestly I don't know if I had that wired up correctly really because I had the standalone R/LG wired to my switched fuse box instead.

Dammit. It's late so I'm going to bed.
 

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Sweet!

It's like they say...the first step to getting it perfect, is to get it good enough. Someone's probably said that before, right?
 

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Like a Phoenix from the ashes!

Fantastic!
 

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Have you went out and annoyed the neighbors yet?

It's looking good!

It needs a TCCoA sticker, tho. :)
 

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Discussion Starter #355
Have you went out and annoyed the neighbors yet?

It's looking good!

It needs a TCCoA sticker, tho. :)
I'm sure that my trip up and down the block did annoy them. It annoyed me too. The car is too loud, the steering is really difficult, the brakes are too mushy and the car backfires too much.

Just a few things to fix.

Is there even such a thing as a TCCoA sticker anymore?
 

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The car looks sick! I love the look of a titanium bird with a black hood. Only suggestion would be to paint the body side moulding piece on rear bumper body color, since the front is already painted and the side mouldings are already gone. As for the TCCoA sticker, send a PM to ClintD. He makes custom decals, and I'm sure he can make one for you.
 

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I have a stack of the ~4x6 ones that Michelle sent me WBW; PM me your addy, and I'll mail you a couple. They last about 10 years before fading.

ClintD makes them out of vinyl, much nicer than what I've got; these are just white lettering on clear.

I think I still have a few of the Lorain Assembly Plant stickers B made. :)


I still have an unused "DirtyDog Performance" windshield banner too. >:)



 

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Discussion Starter #358
The car looks sick! I love the look of a titanium bird with a black hood. Only suggestion would be to paint the body side moulding piece on rear bumper body color, since the front is already painted and the side mouldings are already gone. As for the TCCoA sticker, send a PM to ClintD. He makes custom decals, and I'm sure he can make one for you.
Thanks. It was just dumb luck to get one this color. I much prefer it to Mocha Metallic or as it's also known; High Performance Tan. :|

I'll look into painting those parts at some point. I need to work through my other challenges first. We won't get into the fact that the 15W50 came out of the oil pan like water because of how fuel soaked it was. I'm hoping that since I didn't ever drive the car with it like that nor did I even get the engine completely warm and it's not smoking that no real damage was done.
 

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Discussion Starter #360
Looks like next weekend will be the first autocross event for the car. I've added fuel pressure which seems to have improved the backfire in exhaust issue. I got the alignment done yesterday (by hand) and now I'm pretty much ready to go.

-1 degrees of camber front and back with the rear toe in and the front toe out. Nice racecar setup.

Wish me luck.
 
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