Couple of things I'd do first off...

1. Replace the horseshoe connector on the coil.

You can get a new one at most auto places. Napa, for instance. though you may have to order it. Sounds like the previous owner put his own connections on it. This is of course if you are running factory coils.

2. Check and replace the grounds.

Engine to Firewall Ground. Blue Cable in picture. Bolts to the engine block just below the oil pressure sender, and bolts to the firewall under the throttle cable attachment.



Negative Battery Cable to frame ground. Goes from the negative post of the battery, to the frame. On mine the same cable goes from the negative battery post to the frame, via a crimp connection, and from there it follows to one of the starter bolts. See pic below.



A better way to do this than factory as seen in the above picture is to have a ground cable running from the negative post of the battery to the engine block, or starter mounting bolt etc... and another cable running from the frame to the starter, or engine block.

Hope this helps.

 

The positive and negative terminals of the coil are the small ones. They are the terminals for the primary windings in the coil. The + side wire comes from the ignition switch.

The fact that the condition is only in effect with the door open certainly seems significant, and a likely clue as to where the problem originates. Perhaps you have a hinge interfering with the wiring harness?

Try this: turn the engine on, left turn signal on and then open the door. Does it affect the way the engine runs? Does it effect the interior light?

Your firewall ground is a small braided wire. There may be two, one going to the engine and another going to the passenger side inner fender.

 

Never put a battery cable under a starter mounting bolt ....

Copper crushes allowing the starter to flex on the remaining bolts causing failure, Also they typically don't stay tight.

There is almost always a blank hole on the block.

If you are having Block to Starter ground issues, Pull the starter and CLEAN the mounting surfaces.

-Enjoy
fh : )_~

 

If you have issues with what I said earlier. Ask Ford. This is how they did it at the factory. Not saying there isn't a better way however. But if Ford did it that way, and it's lasted on mine for 28+ years, can't be too much wrong with it. And logically there is a reason why Ford put it there, path of least resistance.

It's not a copper connection, not sure what metal it is, but it isn't copper. It's not lead either. More like steel actually.

This is true.

 

I agree, seems to me it might be either a short to ground, or Poor ground, when the door jam switch operates the dome light, perhaps.

It depends on your definition of small. It's a 8 gauge braided wire, color black originally. Which I'd consider a good size. I replaced mine with insulated cable (pictured above). bolted it to the firewall and engine block, exactly how Ford had the original.

 

Thanks for all the help you guys.I want to reply back to each one of you,but there's so many replies.lol.So i'll try my best to reply to the ones I can remember.Whenever I open the door,there is no difference in the dome light or the way the engine runs.As far as block grounds go,I think the previous owner removed these for some reason.The only cable I have running from the battery on the negative side is the cable to the a/c compressor bracket.I might have a pic.It's hard to tell,but if you look on the side of the alternator,you can see the negative battery cable leading up to the a/c compressor bracket.I'll try to find a pic that doesn't have tranny fluid all over it.(This pic was from when my tranny line popped and tranny fluid got onto the fan and threw it everywhere).

 

The whole point of forums like this are to get everyones opinions and make your own choices!

I don't have an issue with what you say, It's a free country! (or supposed to be) You can believe what you want!

And I will do the same!

If you feel I insulted you or stepped on your toes, I am sorry! I did not mean to do so! I am just voicing my opinion!

Manufactures do not put cables under torqued retaining bolts!
Starter bolts are a torqued retaining bolt!

There is no resistance issue unless the starter is loose or was installed dirty!

They are typically zinc coated Copper or an alloy, they are not steel!

-Enjoy
fh : )_~

 

Here's another closer pic....You can see where the negative cable bolts up to the bracket.

 

I am not sure about a six cylinder, but on the few models I have messed with, the official spot were the large battery ground connects on the small v8's was a hole on the lower front passenger side corner of the block. Very hard to see and get to, right behind the alternator. Right before it it bolted to that spot, it had a band around it were they stripped the insulation, and that part was bolted to the top of the frame rail, sort of below the solenoid area.

On a few trucks also, I have notice a braided wire near one of the passenger side cab mounts. It clips onto the bottom of the cab, and then clips onto the frame, right around one of the body mounts.

One of the grounds to the firewall bolts to the firewall sheetmetal, and then bolts to the rear of the engine. I can't remember though, if it bolted behind a bellhousing bolt, or it had it's own special short bolt that went into one of the threaded holes in the back of the head. This is the one forgotten all the time when the engine is pulled and then replaced.

 

I don't have enough fingers/toes/hair to count the ground straps I've seen/fixed that some idiot left hanging! If only they knew the damage/problems they were causing by being lazy.
(or forgetful, but the forgetful can be forgave!).

Ground straps are not as important on gassers as they are on diesels.
Though as I say that, I forget about todays electronics (I'm old school, I know NADT about todays electronics), They may be as important on the gassers of today.

-Enjoy
fh : )_~

 

Electricity doesn't care what kind of fuel you burn!

Any progress or new clues on the original problem?

 

It has nothing to do with the electrical system!

It's about Static electricity!
A diesel creates static electricity and if not properly grounded it will eat the babbit bearings.

Gassers don't create this static electricity.

-Enjoy
fh : )_~

 

No that's not what I meant. Sorry for the confusion. Think nothing of that.

What I was trying to say is the information isn't only coming from me, it's coming from the Ford wiring manual I have. Which lists every ground, and every connector and connection on the truck and where it goes.

Neg Battery cable (Color Black), from battery (Connector #215), to frame, from frame to upper starter retainer bolt (Ground #203 / 300-I6 Engine)

Positive battery cable (Color Red) From Battery (Connection #214) to starter solenoid (Connection #213), from starter solenoid to positve starter terminal.

Ford did in this application. (Why I don't know.) And the really odd thing is, I looked for a torque limit for the starter bolts in my Ford service manuals and could not find one. It has the listing of every torqued bolt on the engine from the cylinder heads, intake vacuum fittings, to the spark plugs, but it does not list the starter bolts.

Like I said above, I do not know why the difference in the V8 or I6 but that's what the connection and ground chart says above.

 

Well that's definately not factory. That's where your air pump bolts up. That connection looks like it needs cleaned as well. I'd go to the block directly in this case.

Is there any ground cables, wires, straps etc.. going from the engine block to the frame, and firewall that you can see? According to the Diagrams it needs them.

 

You are aware that a leaking tranny line such as yours can ignite on the exhaust manifold and burn your truck to the ground. Aren't you?

I would fix that with some steel line ASAP. Not fuel hose......