Reading plugs???
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From: CHARLESTON, WV 25304
Reading plugs???
I know how to read plugs but this one has me stumped. I have 31000 miles on my 97 4.6. When I changed my plugs last weekend I noticed that the 1-2-3-4 plugs were the light tan just like they should be and they were hardly worn at all. (I almost thought about not changing them when I looked at the first plug I pulled). Anyway to the problem. The drivers side plugs were a whole different story, all of them showed considerable wear on the center electrode. Anyone heard of this before (speaking of the difference in wear)??
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97 4X4 Flareside 4.6 5-Speed, Superchip, ASP underdrives, Airaid, Dynamax headers, Borla Cat-back, 5% Tint, 285/75/16, 16x8 Baha's, Rancho 9000's.
Soon to come:
3" body lift, 315/75/16 BFG KO's
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97 4X4 Flareside 4.6 5-Speed, Superchip, ASP underdrives, Airaid, Dynamax headers, Borla Cat-back, 5% Tint, 285/75/16, 16x8 Baha's, Rancho 9000's.
Soon to come:
3" body lift, 315/75/16 BFG KO's
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From: Trixters-Playground
Remember, half of the plugs are firing under reverse polarity.
Later plugs have platinum on both electrodes, so one part number works on both sides. You need to look for a "PP" designation (double platinum).
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'98 4.6 5-sp F-150
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Later plugs have platinum on both electrodes, so one part number works on both sides. You need to look for a "PP" designation (double platinum).
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'98 4.6 5-sp F-150
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From: Along Lake Erie
Just a note on the DIS... Bot plugs will fire under positive polarity... (How is it possible to reverse the polarity going to the plug... electrify the ground electrode, which would involve electrifying the block?! I think not. ) and both of the plugs connected to the same coil pack will fire on both the compression stroke and the exhaust stroke. The Air-fuel mixture in the compression side is highly ionized, thereby making it the path of least resistance for the arc, whereas the exhaust gasses are not very conductive, leading to a very small spark if any at all occurs. (I know this useless info because one of my instructors works for Visteon and developed the coil pack currently used in the DIS engines... I'll try and find the schematic he drew for me). Now, as for the uneven wear on the plugs... I have no idea. My best guess would be that for some reason, one bank of cylinders is running hot, or something is awry, anyhow. I'd probably take the plugs to a good mechanic and maybe he could give you some suggestions.
-Joe-
-Joe-
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From: Trixters-Playground
GIJoe,
No, one side of the engine does not run hotter than the other.
I won't get into cylinder numbers or firing order.
On the 4.6L each coil pack fires two plugs at the same time. One cylinder is coming up on the compression stroke, the other is coming up on exhaust. This is why the setup used to be called the "wasted spark" system. Some even believed this contributed to emission control, but I do not believe you will find information supporting this.
Depending on polarity, metal would be transferred to either the ground electrode or the center electrode, depending on the direction of current flow.
When this system originally came out, there were two different spark plug part numbers. The last two letters designated which electrode got a platinum tip (ground or side). After this problem was found, new plugs were released. They are designated with a "PP" (platinum on both electrodes). This is the plug you need, and it can be installed in either bank.
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'98 4.6 5-sp F-150
We've come for your Tundra.
Where we started.
After a facelift.
A 2" drop!
F-150online Photo Album
trixters-playground@excite.com
Truckin' Magazine!
[This message has been edited by crash1 (edited 03-28-2000).]
[This message has been edited by crash1 (edited 03-28-2000).]
[This message has been edited by crash1 (edited 03-30-2000).]
No, one side of the engine does not run hotter than the other.
I won't get into cylinder numbers or firing order.
On the 4.6L each coil pack fires two plugs at the same time. One cylinder is coming up on the compression stroke, the other is coming up on exhaust. This is why the setup used to be called the "wasted spark" system. Some even believed this contributed to emission control, but I do not believe you will find information supporting this.
Depending on polarity, metal would be transferred to either the ground electrode or the center electrode, depending on the direction of current flow.
When this system originally came out, there were two different spark plug part numbers. The last two letters designated which electrode got a platinum tip (ground or side). After this problem was found, new plugs were released. They are designated with a "PP" (platinum on both electrodes). This is the plug you need, and it can be installed in either bank.
------------------
'98 4.6 5-sp F-150
We've come for your Tundra.
Where we started.
After a facelift.
A 2" drop!
F-150online Photo Album
trixters-playground@excite.com
Truckin' Magazine!
[This message has been edited by crash1 (edited 03-28-2000).]
[This message has been edited by crash1 (edited 03-28-2000).]
[This message has been edited by crash1 (edited 03-30-2000).]
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From: CHARLESTON, WV 25304
Am I to understand that when these engines were first built that they had different plugs in either side? If this was the case they put the wrong ones in mine or just didn't know to do this yet.
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97 4X4 Flareside 4.6 5-Speed, Superchip, ASP underdrives, Airaid, Dynamax headers, Borla Cat-back, 5% Tint, 285/75/16, 16x8 Baha's, Rancho 9000's.
Soon to come:
3" body lift, 315/75/16 BFG KO's
------------------
97 4X4 Flareside 4.6 5-Speed, Superchip, ASP underdrives, Airaid, Dynamax headers, Borla Cat-back, 5% Tint, 285/75/16, 16x8 Baha's, Rancho 9000's.
Soon to come:
3" body lift, 315/75/16 BFG KO's
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From: Trixters-Playground
Yes, they had two different plugs from the factory. No problem there, though, as they were designated (and installed) based on the bank (polarity).
It is possible the factory installed them incorrectly, but most problems occurred when people (and some techs) replaced them for one reason or another.
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'98 4.6 5-sp F-150
We've come for your Tundra.
Where we started.
After a facelift.
A 2" drop!
F-150online Photo Album
trixters-playground@excite.com
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It is possible the factory installed them incorrectly, but most problems occurred when people (and some techs) replaced them for one reason or another.
------------------
'98 4.6 5-sp F-150
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Where we started.
After a facelift.
A 2" drop!
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From: Along Lake Erie
I'm still not understanding how it is possible to reverse the polarity on a spark plug?!?! The positive electrode will always be the center and the ground will always be the piece the spark jumps to, which is grounded THROUGH THE BLOCK. So, please enlighten me. (I'm not trying to sound pissy, I just don't understand the concept of a reversed polarity spark plug.) Beyond that, how is it possible to transfer metal from one electrode to another? The spark is a transfer of electrons, not metal. Just trying to figure all this out.
-Joe-
-Joe-
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From: Trixters-Playground
When each spark jumps the gap on any spark plug, a small amount of metal is eroded (transferred from one electrode to the other). This is why points were replaced so often, and eventually went away.
When working with FORD DIS, what you need to consider is that each coil is open-ended. In other words, there is a plug and a plug wire on each end of the core of each coil. For the TRITON 4.6L, there are two coil packs, each with two coils.
A complete circuit is necessary for current flow. Both gaps have to be jumped to complete the circuit. Current is only flowing ONE direction.
Current flows out of the coil (+), through one plug wire, through one plug (center electrode to ground electrode), through the engine block, through the spark plug on the other bank (from the ground electrode to the center electrode), through the other plug wire, and back to the coil (-). When looking at one bank of plugs, current actually flows in the opposite direction when compared to the other bank.
What you mentioned about atomization within the cylinder is true, however does not consider cylinder pressure. And remember, BOTH gaps have to be jumped (at the same time).
Hope this helps.
Derek
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'98 4.6 5-sp F-150
We've come for your Tundra.
Where we started.
After a facelift.
A 2" drop!
F-150online Photo Album
trixters-playground@excite.com
Truckin' Magazine!
[This message has been edited by crash1 (edited 03-30-2000).]
When working with FORD DIS, what you need to consider is that each coil is open-ended. In other words, there is a plug and a plug wire on each end of the core of each coil. For the TRITON 4.6L, there are two coil packs, each with two coils.
A complete circuit is necessary for current flow. Both gaps have to be jumped to complete the circuit. Current is only flowing ONE direction.
Current flows out of the coil (+), through one plug wire, through one plug (center electrode to ground electrode), through the engine block, through the spark plug on the other bank (from the ground electrode to the center electrode), through the other plug wire, and back to the coil (-). When looking at one bank of plugs, current actually flows in the opposite direction when compared to the other bank.
What you mentioned about atomization within the cylinder is true, however does not consider cylinder pressure. And remember, BOTH gaps have to be jumped (at the same time).
Hope this helps.
Derek
------------------
'98 4.6 5-sp F-150
We've come for your Tundra.
Where we started.
After a facelift.
A 2" drop!
F-150online Photo Album
trixters-playground@excite.com
Truckin' Magazine!
[This message has been edited by crash1 (edited 03-30-2000).]
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From: Trixters-Playground
Something else- The 5.4L and the newer 4.6L have one coil per cylinder, mounted directly over the plug, and you will find a 12v harness attached to it. No "wasted spark" here.
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'98 4.6 5-sp F-150
We've come for your Tundra.
Where we started.
After a facelift.
A 2" drop!
F-150online Photo Album
trixters-playground@excite.com
Truckin' Magazine!
------------------
'98 4.6 5-sp F-150
We've come for your Tundra.
Where we started.
After a facelift.
A 2" drop!
F-150online Photo Album
trixters-playground@excite.com
Truckin' Magazine!
Senior Member
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From: Along Lake Erie
I found some more info on the Ford DIS coil packs for the F-150. I'll try to scan it in. (How do I post it here? I could probably send it via e-mail, but it's a big file ~ 1.1 Mb or so...) I had a couple of questions still... What is the firing order for the 4.6 engine? Also, since I don't have my truck anymore, I can't check this for myself, but do two of the wires from each coil pack cross over to the other side of the engine? (i.e. do two plug wires from the driver's side coil pack run to the passenger side plugs and vice-versa?) The info I found on the F-150 DIS stated that the coil packs actually contain two double-ended coil packs. If the two positive wires off each coil pack go to the same bank of cylinders, then this whole thing makes sense to me.
This leaves me with a couple of other questions... wouldn't this mean that if you disconnected one spark plug wire, you would actually cause two cylinders to stop firing? How would you check for this? They would be on opposite sides of the engine, I would think... If, for some reason, you lost power to one coil pack, or one coil in the coil pack, would the engine still be able to run?
Also, in the paperwork I found, it does in fact specifically mention that the one bank fires under reverse polarity and that the plugs were initially single-platinum in one bank and double-platinum in the other. This might explain the wear pattern ole blue saw that started this whole discussion. It also stated specifically that the double-platinum could be used in either bank of cylinders when they were replaced.
Please let me know. Thanks. Now, let me go clean the egg off my face....
-Joe-
This leaves me with a couple of other questions... wouldn't this mean that if you disconnected one spark plug wire, you would actually cause two cylinders to stop firing? How would you check for this? They would be on opposite sides of the engine, I would think... If, for some reason, you lost power to one coil pack, or one coil in the coil pack, would the engine still be able to run?
Also, in the paperwork I found, it does in fact specifically mention that the one bank fires under reverse polarity and that the plugs were initially single-platinum in one bank and double-platinum in the other. This might explain the wear pattern ole blue saw that started this whole discussion. It also stated specifically that the double-platinum could be used in either bank of cylinders when they were replaced.
Please let me know. Thanks. Now, let me go clean the egg off my face....
-Joe-