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Could use some diagnostics help

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lynchster View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote lynchster Quote  Post ReplyReply Direct Link To This Post Posted: 03-September-2022 at 6:18PM
I have read about the issues of mismatching coils with ignition systems. I hope I don't have to cut this wire harness open again. I wrapped it like I meant it. Stern Smile

Instead of a ballast I used the factory resistor wire. With just the key on it reads just over 3V. I should check that while running.
I believe I went with a coil for a 76 Gran Torino. I don't remember my previous 76 having an external ballast resistor but this coil does call for use of an external ballast. I assumed my lack of a ballast would be ok since the original points coil called for either a resistance wire or external ballast.  
That said the resistance values of the two coils are different with the older one having higher primary and secondary resistance. 
Would swapping back to the original coil make sense? I'd have to cut off the "horseshoe" clip and install eyelets for that.
Assuming I'm right (I don't) about swapping coils should I close the gap on the spark plugs back to .035?
   


Edited by lynchster - 03-September-2022 at 7:06PM
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Post Options Post Options   Thanks (0) Thanks(0)   Quote lynchster Quote  Post ReplyReply Direct Link To This Post Posted: 03-September-2022 at 6:33PM
I did find a second problem after I tested the coil resistance.
I moved onto the distributor. It's a recurved factory unit. 

First test of the vacuum advance...........fail. Will not hold a vacuum.
This was a "new" distributor that was recurved and certainly appears to be so. When I removed the vacuum advance the exposed portion of the diaphragm is soft and pliable.  
Here's the scary part. Just for curiosities sake I inserted a 3/32" Allen wrench in it and there was nothing for it to adjust in there. I never messed with it previously because I read it was the last thing to adjust if it was even needed. That said, if they are all adjustable, I may have found the cause of the sudden misfire and its fuel related. Or it was never in there to begin with or this on isn't adjustable (?). 
What if this adjustor backed out and got sucked into the carb through the vacuum line? Anyone know if it possible to be trapped in the carb? If it made it into the engine it doesn't appear to have affected the compression any. 

ugh          
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 72FordGTS Quote  Post ReplyReply Direct Link To This Post Posted: 04-September-2022 at 1:36AM
Originally posted by lynchster lynchster wrote:

I have read about the issues of mismatching coils with ignition systems. I hope I don't have to cut this wire harness open again. I wrapped it like I meant it. Stern Smile
   


You are running a blue strand module for Dura Spark II right?  1977 was the first year for DSII, 1976 was a slightly different ignition system, so I am not sure that the coil are interchangeable.  I am kind of leaning toward CJ's opinion that it might be the module failing. Is it an aftermarket brand?  It seems to be tough to get a quality DS module these days which is why so many run an HEI module instead.

Do you have a troubleshooting guide for a DSII ignition?  It might be worth running through that to check everything.  I might be able to dig one up from an old service manual if you need one.  I also think it would be worthwhile to eliminate the gas from the equation by running off your 2 gallon can with fresh gas.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Rockatansky Quote  Post ReplyReply Direct Link To This Post Posted: 04-September-2022 at 4:50AM
not all dizzy vac cans are adjustable,

but as long as it's Censored you might as well open it up and see if anythings missing

trying a GM module swap seems like a valid test?

remember they need a heat sink and the special white grease,
some guys have used the Duraspark case to keep it looking original
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Post Options Post Options   Thanks (0) Thanks(0)   Quote lynchster Quote  Post ReplyReply Direct Link To This Post Posted: 04-September-2022 at 5:42AM
Originally posted by 72FordGTS 72FordGTS wrote:


You are running a blue strand module for Dura Spark II right?  1977 was the first year for DSII, 1976 was a slightly different ignition system, so I am not sure that the coil are interchangeable.  I am kind of leaning toward CJ's opinion that it might be the module failing. Is it an aftermarket brand?  It seems to be tough to get a quality DS module these days which is why so many run an HEI module instead.

Do you have a troubleshooting guide for a DSII ignition?  It might be worth running through that to check everything.  I might be able to dig one up from an old service manual if you need one.  I also think it would be worthwhile to eliminate the gas from the equation by running off your 2 gallon can with fresh gas.

It is a blue strand. I used part numbers for a 1976 Torino. 
I've never heard of a Duraspark box "going" bad only work or don't work.  It would not be the first new thing I've learned.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Steve M. Quote  Post ReplyReply Direct Link To This Post Posted: 04-September-2022 at 7:23AM
Duraspark boxes do act up.on my 1976 S&H replica, the box would intermittently fail. Once the car sat for about 20 minutes, it would start up and all was good u til the next failure. Replaced it with a Wells unit and problem was solved
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Post Options Post Options   Thanks (0) Thanks(0)   Quote lynchster Quote  Post ReplyReply Direct Link To This Post Posted: 04-September-2022 at 8:41AM
Originally posted by Steve M. Steve M. wrote:

Duraspark boxes do act up.on my 1976 S&H replica, the box would intermittently fail. Once the car sat for about 20 minutes, it would start up and all was good u til the next failure. Replaced it with a Wells unit and problem was solved

That's the failure I'm used to. Work or do not work. Not sure it's a cause for the misfire. 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote lynchster Quote  Post ReplyReply Direct Link To This Post Posted: 04-September-2022 at 8:42AM
Originally posted by Rockatansky Rockatansky wrote:

not all dizzy vac cans are adjustable,

but as long as it's Censored you might as well open it up and see if anythings missing

trying a GM module swap seems like a valid test?

remember they need a heat sink and the special white grease,
some guys have used the Duraspark case to keep it looking original

Went out this morning and went digging around with different allen wrenches. Found it where it's supposed to be with a #3 metric. Still doesn't hold a vacuum. LOL
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Rockatansky Quote  Post ReplyReply Direct Link To This Post Posted: 04-September-2022 at 9:39AM
Originally posted by lynchster lynchster wrote:

I have read about the issues of mismatching coils with ignition systems. I hope I don't have to cut this wire harness open again. I wrapped it like I meant it. Stern Smile

Instead of a ballast I used the factory resistor wire. With just the key on it reads just over 3V. I should check that while running.
I believe I went with a coil for a 76 Gran Torino. I don't remember my previous 76 having an external ballast resistor but this coil does call for use of an external ballast. I assumed my lack of a ballast would be ok since the original points coil called for either a resistance wire or external ballast.  
That said the resistance values of the two coils are different with the older one having higher primary and secondary resistance. 
Would swapping back to the original coil make sense? I'd have to cut off the "horseshoe" clip and install eyelets for that.
Assuming I'm right (I don't) about swapping coils should I close the gap on the spark plugs back to .035?
   


3v seems awfully low, i'd expect at least 9v ?
i'd gap the plugs to 035" for a better spark kernel
what plugs, anything exotic double platinum / iridium etc ?


https://www.fordmuscleforums.com/threads/tricky-or-trick-hei-module-inside-duraspark-case.492810/
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Post Options Post Options   Thanks (0) Thanks(0)   Quote handsofstone Quote  Post ReplyReply Direct Link To This Post Posted: 04-September-2022 at 9:54AM
Originally posted by 72FordGTS 72FordGTS wrote:

Originally posted by lynchster lynchster wrote:

I have read about the issues of mismatching coils with ignition systems. I hope I don't have to cut this wire harness open again. I wrapped it like I meant it. Stern Smile
   


You are running a blue strand module for Dura Spark II right?  1977 was the first year for DSII, 1976 was a slightly different ignition system, so I am not sure that the coil are interchangeable.  I am kind of leaning toward CJ's opinion that it might be the module failing. Is it an aftermarket brand?  It seems to be tough to get a quality DS module these days which is why so many run an HEI module instead.

Do you have a troubleshooting guide for a DSII ignition?  It might be worth running through that to check everything.  I might be able to dig one up from an old service manual if you need one.  I also think it would be worthwhile to eliminate the gas from the equation by running off your 2 gallon can with fresh gas.
  Is your vacuum hose going direct to the carb base or ported? I would be surprised if it is in either the carb or engine. I believe the screw has a hole in it anyway and unless the hose was wide open I doubt there is enough air flow to suck it into the hose.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote lynchster Quote  Post ReplyReply Direct Link To This Post Posted: 04-September-2022 at 10:30AM
Originally posted by Rockatansky)<div><br></div><div>3v seems awfully low, i'd expect at least 9v ?</div><div>i'd gap the plugs to 035 for a better spark kernel <br></div><div>what plugs, anything exotic double platinum / iridium etc ?</div><div><br></div><div><br></div><div><a href=https://www.fordmuscleforums.com/threads/tricky-or-trick-hei-module-inside-duraspark-case.492810/ target=_blank rel=nofollow>https://www.fordmuscleforums.com/threads/tricky-or-trick-hei-module-inside-duraspark-case.492810/</a><br></div>[/QUOTE Rockatansky)

3v seems awfully low, i'd expect at least 9v ?
i'd gap the plugs to 035 for a better spark kernel
what plugs, anything exotic double platinum / iridium etc ?


[/QUOTE wrote:



I'm going to test the voltage when running and see what I get.
The plugs are standard autolites gapped at .044. I've been debating about going back to .035.

I'm going to test the voltage when running and see what I get.
The plugs are standard autolites gapped at .044. I've been debating about going back to .035.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Big Bird Quote  Post ReplyReply Direct Link To This Post Posted: 05-September-2022 at 3:00AM
Adjuster screw will not fit down the vacuum line, and yes, Durasparks go bad and work intermittently.
Innards get heat sensitive and only work when cool, or the potting melts and they get vibration sensitive.
Mine, the back of the inner fender rusted out behind it and it would stop working if wet...
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Post Options Post Options   Thanks (0) Thanks(0)   Quote lynchster Quote  Post ReplyReply Direct Link To This Post Posted: 05-September-2022 at 4:36PM
Originally posted by handsofstone handsofstone wrote:

 Is your vacuum hose going direct to the carb base or ported? I would be surprised if it is in either the carb or engine. I believe the screw has a hole in it anyway and unless the hose was wide open I doubt there is enough air flow to suck it into the hose.

It's ported. 0 at idle 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote lynchster Quote  Post ReplyReply Direct Link To This Post Posted: 05-September-2022 at 4:37PM
Originally posted by Big Bird Big Bird wrote:

Adjuster screw will not fit down the vacuum line, and yes, Durasparks go bad and work intermittently.
Innards get heat sensitive and only work when cool, or the potting melts and they get vibration sensitive.
Mine, the back of the inner fender rusted out behind it and it would stop working if wet...

Mine starts and runs it just developed a misfire I haven't sorted yet. 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote lynchster Quote  Post ReplyReply Direct Link To This Post Posted: 05-September-2022 at 4:40PM
Originally posted by 72FordGTS 72FordGTS wrote:


You are running a blue strand module for Dura Spark II right?  1977 was the first year for DSII, 1976 was a slightly different ignition system, so I am not sure that the coil are interchangeable.  I am kind of leaning toward CJ's opinion that it might be the module failing. Is it an aftermarket brand?  It seems to be tough to get a quality DS module these days which is why so many run an HEI module instead.

Do you have a troubleshooting guide for a DSII ignition?  It might be worth running through that to check everything.  I might be able to dig one up from an old service manual if you need one.  I also think it would be worthwhile to eliminate the gas from the equation by running off your 2 gallon can with fresh gas.

I checked on rockauto and a 76 Gran Torino and 78 Granada use the same box and coil part numbers for Standard.  No don't have a DSII guide but I'll check to see if there is anything online.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote lynchster Quote  Post ReplyReply Direct Link To This Post Posted: 05-September-2022 at 4:41PM
Originally posted by lynchster lynchster wrote:

Originally posted by Rockatansky)<div><br></div><div>3v seems awfully low, i'd expect at least 9v ?</div><div>i'd gap the plugs to 035 for a better spark kernel <br></div><div>what plugs, anything exotic double platinum / iridium etc ?</div><div><br></div><div><br></div><div><a href=https://www.fordmuscleforums.com/threads/tricky-or-trick-hei-module-inside-duraspark-case.492810/ target=_blank rel=nofollow>https://www.fordmuscleforums.com/threads/tricky-or-trick-hei-module-inside-duraspark-case.492810/</a><br></div></td></tr></table>
<div><br></div><div>I'm going to test the voltage when running and see what I get. It might be at 3V with just the key on to keep from cooking the coil.</div><div>The plugs are standard autolites gapped at .044. I've been debating about going back to .035.</div>[/QUOTE Rockatansky)

3v seems awfully low, i'd expect at least 9v ?
i'd gap the plugs to 035 for a better spark kernel
what plugs, anything exotic double platinum / iridium etc ?



I'm going to test the voltage when running and see what I get. It might be at 3V with just the key on to keep from cooking the coil.
The plugs are standard autolites gapped at .044. I've been debating about going back to .035.
[/QUOTE wrote:

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Post Options Post Options   Thanks (0) Thanks(0)   Quote lynchster Quote  Post ReplyReply Direct Link To This Post Posted: 06-September-2022 at 1:28PM
Originally posted by Rockatansky Rockatansky wrote:

  3v seems awfully low, i'd expect at least 9v ?
i'd gap the plugs to 035" for a better spark kernel
what plugs, anything exotic double platinum / iridium etc ?



I did retest. 
KOEO  4.46V
KOER  9.98V
I have been reading some articles about plug gaps. I went with .044 based solely on factory specs for engines running stock Duraspark systems. I might try a tighter gap. If not .035 maybe .040.
The thing that gets me is the sudden on set of this problem.



Edited by lynchster - 06-September-2022 at 3:16PM
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 72FordGTS Quote  Post ReplyReply Direct Link To This Post Posted: 07-September-2022 at 2:53AM
Ok, good that you checked that the '76 was the same parts as the '77.  Ford literally changed the electronic ignition setup on an annual basis until the Dura Spark II was released in 1977.

Here is a test chart for the 1976 Electronic Ignition.  I'd run these tests and report back.




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Post Options Post Options   Thanks (0) Thanks(0)   Quote lynchster Quote  Post ReplyReply Direct Link To This Post Posted: 07-September-2022 at 4:53AM
I'll do that. I'm still not sure it's the ignition  but I'm committed to running down the list. I did find the diaphragm in the vacuum advance canister was shot. Weird.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote handsofstone Quote  Post ReplyReply Direct Link To This Post Posted: 07-September-2022 at 10:04AM
That removal procedure doesn't mention blowing any debris away from the base of the distributor or putting the hold down and bolt away from the engine. And do not leave a small socket near the car or it will jump down the hole.LOLWink
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Steve M. Quote  Post ReplyReply Direct Link To This Post Posted: 07-September-2022 at 11:06AM
Place a clean rag in the hole! 
Don't ask.. ...just trust me on this one
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Post Options Post Options   Thanks (0) Thanks(0)   Quote lynchster Quote  Post ReplyReply Direct Link To This Post Posted: 07-September-2022 at 3:20PM
I will be pulling the distributor in a while to check for wear to the gear. But there will nothing left to fall in that hole.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote lynchster Quote  Post ReplyReply Direct Link To This Post Posted: 07-September-2022 at 3:26PM
Originally posted by 72FordGTS 72FordGTS wrote:

Ok, good that you checked that the '76 was the same parts as the '77.  Ford literally changed the electronic ignition setup on an annual basis until the Dura Spark II was released in 1977.

Here is a test chart for the 1976 Electronic Ignition.  I'd run these tests and report back.

The painless harness doesn't map out exactly like that but close enough. I found a .6 to 1 volt drop to the module red wire.
Battery 12.46V key off
Battery 12.11V key on

Module 11.5V key on

Checked it again after running the car and the module is receiving 12.3. Must have just be slightly low from testing.



Edited by lynchster - 08-September-2022 at 6:53AM
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 72FordGTS Quote  Post ReplyReply Direct Link To This Post Posted: 08-September-2022 at 8:57AM
Originally posted by lynchster lynchster wrote:


The painless harness doesn't map out exactly like that but close enough. I found a .6 to 1 volt drop to the module red wire.
Battery 12.46V key off
Battery 12.11V key on

Module 11.5V key on

Checked it again after running the car and the module is receiving 12.3. Must have just be slightly low from testing.



Did you do that module bias test then?  It says that if the voltage is not within + or - 0.1 volts of the battery voltage that the wire likely needs repair.  Maybe check all the connectors on each end of the wire to ensure not too much resistance.  I could see if that module is not getting adequate voltage that this could cause issue.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote lynchster Quote  Post ReplyReply Direct Link To This Post Posted: 08-September-2022 at 10:12AM
Originally posted by 72FordGTS 72FordGTS wrote:

[QUOTE=lynchster]

Did you do that module bias test then?  It says that if the voltage is not within + or - 0.1 volts of the battery voltage that the wire likely needs repair.  Maybe check all the connectors on each end of the wire to ensure not too much resistance.  I could see if that module is not getting adequate voltage that this could cause issue.
That was the test I performed. The first attempt looked like an issue but the key had been on and off all day testing things.
The retest after I ran it for a bit put it at .16V.
 .06 out of range but it's well over 12V.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote lynchster Quote  Post ReplyReply Direct Link To This Post Posted: 08-September-2022 at 10:31AM
I'm going to keep on this and posting. Never know who it may help down the road.

To date:

Pulled the plugs, checked gaps, and condition.
   .044 and reddish. Ran fine before. I'll try going back to .035 as Rock suggested.

Swapped out the distributor cap.

Checked primary and secondary resistance of coil.

Checked voltage at coil key on and running.

Checked resistance of plug wires
     All under 50 ohms per foot

Checked vacuum.
     Steady 15hg but did need 1/2 turn out to steady it.

Checked compression.
     All between 174 and 179 psi

Replaced defective vacuum advance.
     Just because it was found

Checked for manifold / carb vacuum leak with starting fluid.
     Nothing

Could very well be the carb or the module but I'm almost certain it's a motocraft. I personally have never seen a module cause a misfire but one of my favorite sayings is "Don't tell me what it isn't until you can tell me what it is".



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Post Options Post Options   Thanks (0) Thanks(0)   Quote 72 RS 351 Quote  Post ReplyReply Direct Link To This Post Posted: 08-September-2022 at 12:18PM
How old are the plug wires, and how many times have they been pulled off of the plugs? Those are all very fragile, and they aren't that expensive to replace on older cars.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote lynchster Quote  Post ReplyReply Direct Link To This Post Posted: 08-September-2022 at 12:23PM
Originally posted by 72 RS 351 72 RS 351 wrote:

How old are the plug wires, and how many times have they been pulled off of the plugs? Those are all very fragile, and they aren't that expensive to replace on older cars.

It's all "new".  That said the vacuum advance diaphragm was torn anyway.
Checking spark plug resistance now. First 4 are between 5000 - 5100 ohm. Barring operational error I've just about cleared the ignition system.
Chuck
72 Gran Torino Sport
08 Taurus (Maytag)
03 Dakota (Rusty)
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Post Options Post Options   Thanks (0) Thanks(0)   Quote lynchster Quote  Post ReplyReply Direct Link To This Post Posted: 08-September-2022 at 1:26PM
I've thinking about fuel system in the background.

It lacks a gauge and a regulator. The Edelbrock carbs (this one a 1411 750cfm) like about 5psi and a stock pump can do about 7-8 psi. It didn't seem to be a  problem running it under construction or for the first 80 miles but here we are.
Not certain how to reconfigure the fuel lines.
I do have a 600cfm Holley "Warrior" sitting around that was rebuilt years ago and never used but the fuel line is all wrong for that at the moment too.

Chuck
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Post Options Post Options   Thanks (0) Thanks(0)   Quote lynchster Quote  Post ReplyReply Direct Link To This Post Posted: 08-September-2022 at 3:57PM
Originally posted by lynchster lynchster wrote:

Originally posted by 72FordGTS 72FordGTS wrote:

[QUOTE=lynchster]

Did you do that module bias test then?  It says that if the voltage is not within + or - 0.1 volts of the battery voltage that the wire likely needs repair.  Maybe check all the connectors on each end of the wire to ensure not too much resistance.  I could see if that module is not getting adequate voltage that this could cause issue.
That was the test I performed. The first attempt looked like an issue but the key had been on and off all day testing things.
The retest after I ran it for a bit put it at .16V.
 .06 out of range but it's well over 12V.

I was looking over those sheets you posted and did another test. I'd like to start the car again but it's almost 11pm.

Battery down to 12.28V
Module bias - red 11.76
Voltage - green 12.17

The key on power supply is an unused plug I believe for A/C in cars that have it. I used it for the choke and the module since it didn't involve cutting and splicing. It currently test at 12.24V

Until I can start it again I'm going the bypass the key on power supply of the factory harness and go to the battery. Maybe there is too much of a drop there.

Edit: I did the bypass and it eliminates any meaning full voltage drop. All but matches battery voltage. Not what I was hoping for. It appears I'm going to have to irrevocably tap the harness somewhere.




Edited by lynchster - 08-September-2022 at 4:04PM
Chuck
72 Gran Torino Sport
08 Taurus (Maytag)
03 Dakota (Rusty)
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