82 F150 Parasitic Draw Electrical Question


New member
So I am restoring an 82 F150 with the I300, and struggling to get it running. It is bone stock right now, but the I300 in it is not the original motor. It will run if you give it throttle, but it will not idle. It has the feedback carb, and the distributor with the module mounted directly to the side of the distributor. It also has a parasitic draw that kills the battery if it is hooked up. I'm trying to resolve the draw problem to eliminate any associated electrical problems that may be associated with the difficulty with idling. I understand the basics of electricity but definitely minimal experience with automotive wiring other than plugging in a new part.

Here's what I have found with the draw:

Doing a draw test by pulling the neg battery cable off with a multimeter - I get .6 miliapms of draw.
Pulled all the fuses with no change.
The starter solenoid has two wires hooked up with the red positive - if you disconnect the yellow one, the draw drops to around .25.
Traced the yellow wire - I think it goes to the EEC Relay under the dash. Unplugged the relay, no change still .6. The wire definitely runs with the massive wire bundle under the dash to either the EEC relay or the big plug with like 25 wires in the middle of the underdash.
Tried looking in my Chilton's at the wiring diagram and that wire seems to be labeled "marker relay" but again - not an expert on auto wiring.
One other thing is that one of the solenoid posts has no wire on it - the little one next to the black cable that runs to the starter.

So now I'm stuck - to start with - what is an acceptable draw? .6 miliamp does not seem like a lot, but it will go dead over night. Is there a wire that should be hooked to the solenoid?

Any thoughts or help would be much appreciated!


VIP Member
Do you really mean 6/10 of one milliamp or 600 milliamps? If it only draws 6/10 of one milliamp that could be something as small as the radio keep-alive memory or the ECU keep-alive memory. It should go a long time at that rate without killing the battery. Six hundred milliamps, on the other hand, is a sizeable drain.


Well-known member
0.6 milliamps or 0.6 amps? A 0.6 milliamp load on say a 50 amp hour battery will last for 83,333hrs. 0.6 milliamps is basically zero, within margin or error, maybe a clock in a radio running....

Anyways could the alternator not be charging or the battery toast? Run the truck for a bit, disconnect the battery, leave it for say 15 min and check battery voltage with the multimeter and report back. If you have a bad alternator diode I think you should get an AC voltage reading at the battery while the engine is running (I don't remember the acceptable amount off hand).


New member
Thanks for your replies - so yes it was reading .6 milliamps from what I can tell.

So I went out yesterday morning and tried the test again and it read 3-5 miliamps and it was jumping all around. After a few minutes it stabilized at around 1.0 milliamps and stayed there. The only thing that was different from before is that I had untapped some of the wires to try to trace them back to the firewall. The battery is new and checked out at 12.6 DC volts.

So I crank the truck to see about the alternator charging - it does not idle well at this point but I get a reading of 12.9 DC Volts at the battery with the alt charging at idle. It barely will idle without throttle, so with throttle it was reading 13.9 DC V at the battery. I did this test with the battery connected but the truck running. Immediately after I shut the truck off, the battery is reading at 13.8 DCV instead of 12.6. Not sure if this is normal or if it is overcharging. Also unplugged the negative and it ran exactly the same. I can't say it ran for 15 minutes with the negative unhooked but it's not idling right anyway. Definitely ran for 5-10 at different points.

I will also add at one point the alternator wires were not hooked up correctly and it may have zonked the old battery which is why I thought it had drain in the first place. Now that the battery has been replaced and the alternator is wired correctly, I have not left the battery plugged in overnight because I don't want to ruin another battery.

After all of that I tried to improve the idle - put a timing light on it and don't get a consistent flash ... and realize the idle doesn't change if I entirely unplug #1. So I swap out the plugs and wires with a fresh set and get a consistent flash on the timing light and get it timed at 10 degree BTDC per my Chilton's.

At this point obviously it is idling much smoother, but still struggling. I have a Vacuum gauge on it it at the manifold and its reading between 10 to 14 but smooths out with throttle ... responds pretty well and with throttle it goes to around 20 on the vacuum. As it warms up and I guess the feedback carb system gets to work the idle seems to change - smooths out and it seems faster to me but there is no tach on it (No adjustment by me to the carb at this point) and the vacuum goes into the 19-20 range. However - when this smooth idle state starts, it totally tanks if you give it throttle where as before it would only run smoothly with the throttle. I continue fooling around and it cuts off and at this point it will not recrank.

So while I am there after it cuts off and the ignition switch is still there is some kind of whirring sound or clicking coming from the carb area and a clicking or buzzing from the distributor. It does it for about 2 seconds and stops. I swear that I have heard the same sound when the battery is connected but the ignition is off - so back the parasitic draw - is it possible that however the feedback carb and distributor has been wired in is causing the solenoids in the feedback carb to move while it is off draining the battery but only doing it sometimes? Pretty sure the carb and distributor don't belong in an 82 and I didn't do the wiring....

Thanks again.


VIP Member
:hmmm: I have an 84 F150,and had similar problems.Finally got fed up with the electronic carb and all the junk that went with it.Swapped the whole mess out for the DS2 setup and was very satisfied.My cost for the DS2 was ZERO.It was given to me.No cutting or splicing of wires was required,as all of the plugins were in the main wiring harness of my truck for the ignition box and distributor.Installation,Including the time to drive to a friends house to borrow his timing light was appx 2 hours.
Mileage went from 8 on the road to 16 on the road.Much easier starting and much smoother idle and running.
Good luck.Have fun.Be safe.


Well-known member
Have you checked compression? Checked for vacuum leaks? Pull the spark plugs and have a look at them. Carb set correctly? How old is the gas and fuel filter?

Another thing you can do is put on some big gloves and pull one plug wire at a time, the engine should bog down for each one to show everything's working properly. May give hints. Be careful if you do this.

Carb may just need a rebuild. The duraspark 2 system is great of can switch the carb and ignition over in your state.


New member
Thanks for the thoughts- so I am definitely considering the DS II conversion as a next step, but need to read up more to pull the right parts etc.

Over the weekend I changed the plugs and wires- before the change the #1 plug would not flash the timing light, when I pulled the plug there was basically no change in the idle. Plugs were fouled with heavy black carbon... maybe too much gas. So changed those and it helped plus I was able to time it at that point. I guess I could pull the new plugs to see if there is anymore change- but like I said the idle got really smooth and the vacuum got in the right range, but it totally bogs with throttle which seems like a carb issue to me. That was only after it warmed up and seemed to smooth itself.

Plus I’m curious if all the clicks and whirring from the dizzy/ module and the feedback carb are normal when the switch is on/off. I have very limited understanding about the feedback carb.

Finally back to the electrical- is it normal for the battery volts to be up after running the truck and to gradually come down? So a charged battery should be at 12.6 v. But immediately after shutting the truck off mine was in the 13.5 range. After i went to the store for plugs and checked it it was coming down. I don’t want to ruin a battery. Autozone tested the alt previously and said it checked out. Have not done anything with the regulator.


Well-known member
There are 2.2 volts per-cell in a lead acid battery so a fully charged battery should be 13.2VDC. If the alternator is working it should increase to around 14.7 under light throttle or about 2000rpm. The problem your having cam still be ignition. You didn't say anything about the condition of your cap and rotor or the coil. Visually check cap and rotor and perform an ohm test on the coil I can't remember the ohm values but they are like .8 and 1.5 ohms. I usually just replace that stuff as I have parts around. When you give it throttle does it pop or just lay down? Give your plugs another check and see if they are wet or black good place to check. Good luck


VIP Member
F15082":cr77ljdw said:
I get a reading of 12.9 DC Volts at the battery with the alt charging at idle

F15082":cr77ljdw said:
So I went out yesterday morning and tried the test again and it read 3-5 miliamps and it was jumping all around. After a few minutes it stabilized at around 1.0 milliamps and stayed there

F15082":cr77ljdw said:
Immediately after I shut the truck off, the battery is reading at 13.8 DCV

On an older vehicle, up to 150 mA is what I consider acceptable. A draw of 3-5 mA will not kill a battery in short time. It's possible to have an intermittent draw that's simply not there when you are checking. I know the battery is new, but it's possible for batteries to have internal shorts that will not show up on draw testing.

Fords usually charge at 14.4-14.8v, typically a bit higher than other makes. A dead battery (or significant load) can cause the charging voltage to drop at idle, at least until the battery charges or the load goes away.

The 13.8v at the battery immediately after shutting off can be surface charge. try pulling the headlamps on for a few seconds to get rid of it.

How long does it take for the battery to die? If it's dead overnight, suspect a shorted diode in the alternator. If it takes several days, it's more likely to be a low current device like the radio, glovebox lamp, door lock switch, etc...


New member
So the battery does drop back to 12.6 over a couple of hours.I just want t make sure that over charging was not hurting the battery because something ruined the previous battery.

As far as how long to kill it- it was over night, but previously the first time it happened the alternator as not hooked up correctly. Since everyone is saying 3 mil amps is not a significant draw I’m thinking one of two things- 1. The bad alternator hookup was the cause of the draw/ appearance of a draw or 2. The feedback carb solenoids are coming on intermittently. I’m sure I have heard that buzzing sound when the ignition is off.

Since the battery died before I fixed the alternator- I only left it hooked up once ... but the battery had been ruined i think. I thought it went dead, but now I’m thinking it wouldn’t hold a charge. Now, I don’t leave it hooked up over night, so I don’t really know that it still drains at this point.

It definitely still is having trouble running though - I have not tested the coil, and can try that next. I have checked the cap for cracks but nothing beyond that. The is a small crack where the module mounts to the distributor, just around the screw I think and it does not appear loose.

GPGoverMPG":1sb95hrc said:
When you give it throttle does it pop or just lay down?

It just goes out, no pop or back fire, almost like there is not fuel to keep up with the air. Again - the funny thing to me is when I first got it timed, it ran best with more throttle. It smoothed it’s own idle, but would not take throttle at that point. When it cut off it would not crank again.


New member
So I tried a totally new method today and discovered there is definitely a draw and it has something to do with the EEC- Hopefully if anyone can help it might help someone else with a similar problem.

Today I hooked the battery up at 8:30 and tested the draw and the battery charge / volts without running it with the following results. Also got a new multimeter because the other one was cheap and old and was seeming to give inconsistent numbers on the amp draw. The ignition was off through out -
8:30 - 12.6 DCV, 0 Amp draw
9:30 - 12.6 DCV, 0 Amp draw
10:30 - (this is where it gets interesting) - 12.4 DCV, .78 Amp (not miliamp) draw. What I find is the following - every time I touch the negative battery cable to the battery I hear a click, it is coming from one of the solenoids on the side of the carb. I think it is the feedback solenoid - it's vertical on the right side of the carb. I disconnect it. Clicking stops and the amp draw drops to .5. Still hear a different click very faint, finally find it coming from the cab. The EEC relay is clicking each time to touch the negative to the battery. I disconnect the EEC relay. Amp draw drops to 0 and no clicking. Reconnect the "feedback solenoid" (or whatever it is) and still a zero amp draw.
11:00 - 12.5 DCV, 0 Amp Draw EEC disconnected
1:45 - 12.5 DCV, 0 Amp Draw EEC disconnected

So - The EEC has something to do with the parasitic draw. There is a lot of good information here about the EEC: https://easyautodiagnostics.com/ford/4. ... ay-tests-3
I ran all of the tests there and found that the hot wire from the solenoid is feeding the “out” wire to the fuel delivery system all the time whether the ignition is on or not. Like the relay is stuck open all the time. I also found that the wire from the ignition switch is functioning properly - that is it is hot when the ignition is on and off when the ignition is off.

So I got an EEC from O’riley - but it has an extra prong in it. Which is in an empty wire spot on the other plug. I try that one and the amp draw disappears, power is no longer going to the “out” wire When the ignition is off - but now there is no power to the out wire when the ignition is on. Also, the ignition wire is no longer hot with teh ignition on.

I am guessing this is not the right EEC ... but is there a differnt explanation and how can I find the right one? Also is it possible that the whole thing is just wired up incorrectly? I don’t understand exactly where that “out” wire goes with the power. Obviously it has something to do with teh feedback solenoid, but is that the only thing? I haven’t tried to run it with out the EEC, but could that work and if this is the problem could it be causing the bog down with the throttle?

I’m guessing that a DSII conversion and removal of the feedback carb would get rid of all the feedback carb stuff as well as teh EEC...


Staff member
VIP Member
Since the feedback wiring and EEC were swaped into your 82 truck there is the chance it wasn't wired up correctly. You will need to determine what year this carb, distribitor, and feedback control system EEC parts are, then find the correct wiring diagram for that system, start checking out any additions or mods that may have been made to the wiring. To me there should only be a small power draw to keep the memory in the ECU, and everthing else should be off. Good luck (y) :nod:


VIP Member
Sounds like a short in the VPWR circuit.

VPWR comes from the ignition switch in 'run' and 'start'. It powers up (and turns on) the EEC relay, carb solenoid, TAB and TAD solenoids, throttle kicker (if equipped), tach (if equipped).

The EEC relay will most likely have on the small pins (coil side), a black/green wire that's grounded all the time, and a red/yellow wire that *should* power up with the key in 'run' and 'start'. If it's hot all the time you will have to check it at the ignition switch. Ford sometimes changes the color codes, but checking both pins will clue you in to which is which. Don't worry about the switched side, you are trying to find out why it's applying with the key off.

Also check all the components above. One of them may have been wired straight to 12v, shorting VPWR to battery.


New member
Thanks for that infor MechRick,

I will read up on VPWR ... got most of my info about the EEC here - https://easyautodiagnostics.com/ford/4. ... ay-tests-3
but it seems to fit with what I am seeing.

Basically what that site says is that the hot wire comes from the starter solenoid and always has power. There is a wire from the ignition that only powers when the switch is on. There is a ground. There is the “out” wire to the fuel system that should only have power with the ignition on. The way the thing works is when the ignition wire powers on with teh switch - it closes the relay circuit and the “out” wire powers on with the power from the Solenoid wire.

So what I found is - the solenoid wire is coming form teh solenoid. It is always hot.
The ignition wire is only hot when the ignition is on.
The “out” wire is hot all the time whether the ignition is on or not.
I did not test the ground.

I will definitely try to track down teh components you list and test the power at each one. Is is possible that the EEC is just staying open all the time even without power from the ignition? I would like to think this might be as simple as replacing th EEC. The ignition wire seems to only come on when it should.Like I said I tried replacing the EEC - but the one I got had an extra pin in the empty spot and the ignition wire no longer seems to come on with teh new switch - so maybe differnt EEC ?

Here’s a picture attached.441C7F6D-9B2A-47A4-A26D-26BFC0A7B104.jpeg


VIP Member
From your image, it seems like the primary (coil) side of the relay has the correct signals. Try unplugging the relay and checking the red (orange?) wire for power, to rule out (or confirm) a short to VPWR.

Does the relay click when cycling the ign on/off?


New member
Thanks again for your thinking - auto electrical is not my strong suite.

So - yes it clicks whether the ignition is off or on - on New Years - I hooked the battery up at 8:30 am and no clicking no draw checked it every hour - until around 10:30. As soon as I unplugged teh EEC the draw stopped.

I can’t really see colors so not 100% sure which wire is red / orange -but Ill call it top left, and bottom left, middle an right ... Here’s what I found about your questions -
With the EEC unplugged -
The wire from the starter solenoid (yellow?? Top left) is still hot.
The “out wire” (bottom left) is not hot with teh EEC unplugged. (It’s always hot when it is plugged in)
The bottom middle wire is NOT hot with teh ignition off or with the ignition on
The bottom right wire IS hot with the ignition on, but NOT hot with the ignition on

To be clear. That wire on the bottom right that is hot when the ignition is on is the one I thought was the ground based on the info on that site (and in my picture...). As I stated before I did not test the ground before, so not sure what it does with teh EEC in - but the middle wire is definitely hot if the EEC is in and the ignition is on (but middle is NOT hot with the ignition off and EEC in).

So maybe the ignition wire is the bottom right wire? Or maybe the whole thing is wired wrong ... that site is pretty clear that the middle wire comes from the ignition and the bottom right is ground if the info on teh site is right.

If the ignition and ground wire in the plug are backward that might explain why the new EEC switch didn’t work - since it needs power from the ignition to close the circuit.

Is there anyone who knows if ground should be in the middle? Is there a way to check it out?

Thanks again!


VIP Member
Are you checking with a voltmeter?

If so, just set it to DC volts, grab your two test leads and check the primary (coil) side for ~12v key on, and 0v key off.

Primary side is the bottom right and middle wires in your image.

Your red lead will tell you the polarity to determine which is ground (if it shows a negative symbol, that's your ground).


New member
MechRick":gl3p4x37 said:
Are you checking with a voltmeter?

Yes using a voltmeter. Since the thread started I got a new one because reading the amp draws my old one was fluctuating a lot. It was old and a cheap one to start with.

MechRick":gl3p4x37 said:
Primary side is the bottom right and middle wires in your image.

So the middle wire is ground and the right wire is hot with the ignition on only. It reads -12v if the red lead is on the middle wire and 12v if the red lead is on the right wire. With ignition off - there is nothing on the primaries.

Not sure how reliable this site is - https://easyautodiagnostics.com/ford/4. ... ay-tests-1
but it clearly says the ground should be on the bottom right, not the middle position.

After that- I think I’ve resolved it thanks to some of the tests. I will explain to help out anyone who runs across something similar. Th new EEC has a little wiring diagram on the side of it. See attached. The numbered prongs cant be seen in the photo but I wrote them in. I think it says that the middle wire, #2, should be the hot wire from the ignition. #1 on the far right should be ground. When the ignition comes out it will complete the circuit between 3 and 4, correct? As I understand it - that is what the relay is supposed to do.

So- According to that, the way was wired had the ground and the ignition wire backward. When I swap them, the new switch is functioning as it should and the wire going out to the fuel system is not staying hot all the time. The old switch still just stays open all the time-Maybe having them swapped killed the old eec. Or maybe it was wired differently.

Parasitic draw seemed to be resolved no draw, ignition wire come on when it should... hot wire is always hot... wire to the fuel comes on when it should. It runs better, but still crazy rich, so I may still try the dsii swap as a next step. Thanks all for all you help.


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