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Coil Failure(s)

Bob,
I understand you supporting your countryman. Even when he is wrong &/or changes his story....
Read more carefully. The discoloured resistor I mentioned I said looks burned: NOT was burned. I said ONE reason [ for the burned look ] was that it might be underrated [ in wattage ]. Get the facts correct....you are always calling for facts.
And do not blame others for 'word wars' when you fan the flames...
 
DS,
I argue when I see bullshit. I see your story has changed now in post #39. There is no such thing as partial truth. Something is true............... or it isn't. So some overseas ECUs are NOW OK??
In the above pic of the 'cheap' cct board, what exactly is 'cheap'???? Yes, it is a different shape & design, but why does that make it cheap if it does the job? I see no problem with it unless it has dry solder joints or broken copper tracks. It is typical of modern cct board design, & I have probably seen more cct boards than you have had hot dinners, 40 + yrs in electrical/electronics & 6 yrs at trade school. Less components does not automatically mean a reduction in quality or capability. It may do, but it could also be an improvement over an original design.
Just nonsense about the EMI. As I said earlier the case provides EMI shielding plus, the metal base [ fender? ] it is bolted too. Go to www.worldphaco.net & have a look at the enlarged view of a HEI module, no shielding. It is only 3" way from the ign coil that emits large spikes, much closer to the EMI source than a Chry ECU mounted on a fender or f'wall.
Agree the source of coil over heat is current, but your explanation of how it occurs [ post #33 [ is wrong.
 
My story did not change, and to me you clearly do not know what you are taking about, and your trying to quote stuff is irrelevant to me. You constantly change what you need to, to justify your comments. Believe what you want, but it you go and read Chrysler training manuals, and manufacture literature like Bosch and such, along with really good tech articles on ignition you might learn something. You seem to be the BS artist around here. Decades in electronic now, decades in car repair, what have you not done? I could wow you with my background too. If you can't tell a quality PCB from a cheap one I hate to think what you were working on.
You just don't understand EMI and signal noise at the component level. Even a resistor can generate a noise. Read some tech documents from the resistor manufactures like Vishay and others. The ECU is being hit with voltage pulses constantly from the firing events. I am not talking about ignition noise on your radio. The noise actually generated inside the ECU.

I gave you concrete reason: Poorer quality pcb with poor traces, no heat transfer area or emi shielding in PCB. Component mounting. Failure to heat sink power transmitter other than friction, poor compound sealant, poor component selection using standard carbon resistors when different type can be called for based on circuit parameters. Poor ground connection. I never said is bad because of "fake transistors" or because it uses later components.

You always have snide remarks and tend to denigrate others because you just have to call BS when you see it as you say. And you are never wrong in your mind. What does country man have to do with it, chip on shoulder?
 
Dave

3F5A8AD6-5B1F-421C-8157-899668EE5ECB.jpeg
 
DS,
The BS continues from you, distorting things I say. I am always learning & always wanting to learn. I have both the Bosch 3rd & 9th edition Auto Handbooks, 2396 pages in total. Happy?
We should re-name you the red herring king with all the red herrings you try to introduce to deflect from the BS: like resistors generating noise. Not an issue in this case. The nonsense about poor quality carbon resistors; they look the same type on both cct boards, & you cannot tell the quality from looks alone. So how do you know they are poor quality? Where is the poor grd connection?
I have covered your other nonsense, but you have yet to explain why the newer cct board is 'poor'. Because it looks different? You say 'poor traces'. I presume you mean the etched tracks. As long as they have sufficient CSA to carry the current, are well secured to the substrate, no dry joints then they are just fine. That board is typical of modern day cct boards, millions/billions in use.
And the BS about fewer components used. It is obvious the newer unit has different circuitry. I see a large yellow cap on it that the factory board does not have. Electrical ccts & printed cct boards often go through revisions & upgrades for various reasons.
If the newer board performs the same electrical service that the original did with less components, then that is a GOOD thing, not a bad thing. It has less solder joints to fail & less components that can fail, & that makes it more reliable.
 
I answered all your questions twice you still default to some defense of a device you know nothing about except from my picture. You make up reasons it is just as good. Nothing I stated is in correct wrt possible faults the coil is seeing if they are failing rapidly in his car. Nothing I stated is incorrect about the quality of those boards and the environment they operate in. It is well document how some of the aftermarket ECU were junk and failed quickly.

You can't just say I disagree "I think it is good enough". You have to make arrogant statements and try to denigrate others, snide remarks that are not called for, and constantly spout how you know more because you do this and did that at nauseum. We all can get grouchy at time, but you seem to thrive on it.

I was just giving the op some possibilities as other did and responded to Bob's post. Believe what you want.
 
Yes it does. One side is full 12v (for starting), the other is I think about 9v (for running). Put the coil on the wrong side and you run full 12v all the time and probably reduce the coil life.

View attachment 1369923

Forget left or right side. Turn it upside down and the right side becomes the left side.
Only thing wrong with this diagram is the missing ground on the orange box. Probably what started this thread.
 
If you look at my picture that is part of the problem with the orange box internal ground. It is a single ground point via that floating metal heat sink that attaches via one of the fake transistor housing screws. The OEM unit has two welded tabs to the cover that then attach to the PCB are bent over and then soldered. You can see the slots on the side of the PCB.

So even if housing is properly grounded, you may have a poor internal ground and it certainly had a poor method for heat sinking the power transistor in the orange box. We have had several orange boxes fail on the run stand even with a separate ground wire attached to the box with the external tooth lock washers to bite into the case. The spark goes very weak making starting hard. Swap the box with a new and hotter spark returns.
 
Post #47.
Dragon Slayer. There you are saying this about me: accusing me of making snide remarks & arrogant statements [ exactly which are those? ] & claiming I denigrate others [ who are they? ] ; that I am 'grouchy' [ a snide remark? ] ; claim to know 'more'; 'you might learn something'.
Your hypocrisy is simply breath taking!!!

Maybe I do more know, that is for others to judge, but I never said I know more. I know what I know from years of experience in various fields, which might be more than you.
And that is your problem; there could be someone on this forum who knows more than you...& you don't like it....So you make all these claims about me mentioned in the lines above & denigrate me. It's called hypocrisy.
I kept personality out of my replies & concentrated on the technical stuff, provided examples etc to support statements.
 
A couple of you guys (you know who you are) are not much help to this thread. PM's are better use for airing dirty laundry. Tech info is handy but ego info, not so much.
 
It was a mild day today, so I got the car out, and with my wife's help I got some measurements as suggested.
Battery Voltage. 12.6V.
Voltage Regulator. 13.8V @ 2000 rpm.
Ballast Resistor 10.5V / 7.5V@ idle
12.5V / 9.1V @ 2000 rpm.
ECU to Battery - post = 0 ohm.
Coil + Post @ start. 7.5V
@ run. 12.5 V @ 2000 rpm.

Car starts right up and runs well right now. I think voltages seem to be all right. I have a spare ECU, but it is a chrome box. I used to run it all the time, but there was some discussion that it could be too "hot" for just regular cruising. I used to run the car down the 1/4 mile occassionally but no longer do that. Thanks again for everyone's interest and recommendations.

I screwed this up yesterday. I rechecked today, and voltage at coil positive post is as follows: 7.7 V. at idle, 9.1 V. at 2000 rpm. Sorry about that.
 
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It was a mild day today, so I got the car out, and with my wife's help I got some measurements as suggested.
Battery Voltage. 12.6V.
Voltage Regulator. 13.8V @ 2000 rpm.
Ballast Resistor 10.5V / 7.5V@ idle
12.5V / 9.1V @ 2000 rpm.
I'm still curious about the ohm reading between Neg post and your orange box case. Bet it is high.
 
I'm still curious about the ohm reading between Neg post and your orange box case. Bet it is high.
It ohmed out as "0" , so it has good ground. I made sure it has clean ( no paint ) mounting points.
 
I know that. It just wasn't shown in your diagram on post 22. IMO, that is the biggest problem with all the complaints about the orange box failures.

It was a mild day today, so I got the car out, and with my wife's help I got some measurements as suggested.
Battery Voltage. 12.6V.
Voltage Regulator. 13.8V @ 2000 rpm.
Ballast Resistor 10.5V / 7.5V@ idle
12.5V / 9.1V @ 2000 rpm.
ECU to Battery - post = 0 ohm.
Coil + Post @ start. 7.5V
@ run. 12.5 V @ 2000 rpm.

Car starts right up and runs well right now. I think voltages seem to be all right. I have a spare ECU, but it is a chrome box. I used to run it all the time, but there was some discussion that it could be too "hot" for just regular cruising. I used to run the car down the 1/4 mile occassionally but no longer do that. Thanks again for everyone's interest and recommendations.
You should not have 12.5V on the + of the coil in run. Ignition 1 has battery voltage to input of the ballast and therefor a voltage drop to the + of coil. During start ign 2, the coil gets full battery voltage less the system voltage droop from the starter amps cranking the motor causing voltage droop at battery. Once starting complete the voltage should drop back to the ballast output value. If the start wire at ballast stays hot after back into run, may have bad ignition switch. Or some other wire fault if ballast has been jumpered.
 
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I think he means that at 2000 rpm he is getting 12.5v on the input side of the bal res & 9.1v on the output side. Voltage has increased from the idle voltage readings because the alt is charging at 2000 rpm.
 
The ballast should drop the voltage. There is a confusing result as I look at the data again. If the ballast has 12.5 and 9.1 (input/output) at 2000rpm the coil positive should be 9.1 at 2000rpm. He states + coil has 12.5 at 2000rpm. So somehow, he has the coil + on the wrong side of the ballast. Or the results are misrepresented. Where does the wire from the 9.1V side of the ballast go? The coil + can't have that high of a voltage input during run unless the ballast is jumpered.
 
DS,
The voltages in question look ok to me.
[1] The 7.5v@ idle & start: at the coil [+] & bal res connection. Less than the 2000 rpm reading because the alt is not charging & adding voltage.
[2] The bal res is dropping the voltage as designed, about 3v.
[4] 12.5v at the bal res input side, engine running & alt charging. Might have expected slightly higher voltage, but over the years electrical devices might have added [ stereo? ] & connected to ign 1 which could cause some voltage drop, lower voltage.
[5] The 9.1v from the bal res goes to the coil [+] terminal.
[6] The coil has actually lost voltage, not gained, in the run position. At idle, 3.0v is dropped across the bal res; at 2000 rpm, 3.4v is dropped across the bal res, leaving less voltage across the coil.
 
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