First of all thanks for even taking the time to read through this.

Now to the point, I have a 93' f150 xlt 302 E4OD. When I am driving at night with my my regular driving and running lights on, my stereo on (stock sound system except for the headunit), and my blower on anything higher than the lowest setting, when idling at a stop I can watch my voltmeter on the dash slowly creep down close to 8. Quite scary, although it does stop before it hits the 8 volt mark and has never died at a light for this reason. But if I turn the blower to low or off it is fine. Keep in mind though as long as the lights are off even with the blower on high i have never had this problem. Is this normal or could this be part of my bigger problem?

The bigger problem:

Every blue moon my truck will not start but its not quite that simple. Basically I'll open the door, dome lights on and everything is normal. Then I go to start my truck and I'll hear the clunk of the starter solenoid and at the same instant I loose power to absolutely everything in the truck. The warning ding, the dome lights, brake lights, headlights, everything is dark. It will stay dark after this for a long time and the started solenoid doesn't even click anymore.

But wait, it gets weirder...

To get it started I basically have to leave something on and wait. Say if I leave my dome light switch or headlights switch on(the lights are not actually on at this time) and walk away I can come back in around 7 min and all the lights will be on and working properly. What in da heck!!! At this point I can usually start it but it runs like crap. Took a video of this below.

Crazy Truck **** - YouTube

After this I'll let it sit for maybe an hour, or a day and it will literally fix itself. Happens around once every two months and have no clue what causes it. FYI I had the whole charging system tested and it tested great, new starter not too far back with a lifetime.

Sorry for all the painful reading but there are so many crazy symptoms I just had to include. Thanks in advance, you guys are the best.

 

I had the same problem with my 92 not to long ago at startup the volt gauge would read normal untill i hit the lights or blower then it would jump just like yours. I cant tell you exactly whats wrong with your truck, however i can tell you what fixed mine. One day i had the no start issue like you even after a new starter so i opened the hood and decied to wiggle the big red wire comming of starter, It easily broke right off... So I ordered a replacement from battery to starter solenoid to starter and BAM Fixed. While i was doing cables i also replaced the main ground to the drivetrain and PROBLEMS FIXED! My truck started so much faster no flashing lights although i also replaced the alternator at the same time due to a loud bearing. This should give you a good start good luck and be careful looks like things are spiking pretty good!! Let us know how things go!

 

Most likely the culprit was the ground cable. Go there first, all you have to do is take the cables off clean and inspect, apply electrical or white lith grease and re install. It doen't cost anything. Do the same to the chassis ground.

 

Speak of the Devil himself!!!!! Right after I posted this I went out to my truck to get on with the rest of my evening and it happened, that evil click. But I was able to start it after waiting for the headlights to light up and then i started it with the lights on. The weird thing is that now my dome light is blinding bright, headlights are brighter than ever, and I can turn everything on without any voltmeter problems. I have a feeling it cycles, meaning that when the problem occurs when I can finally get the truck to start it works perfect but then slowly starts to show more symptoms and get closer and closer to not starting until it just doesn't start. I do need to fix this though before it strands me somewhere.

Donniezyea:
It's really nice to have input from someone who has had this problem before and knows what I am talking about. Thanks. Funny you suggest that because I have been meaning to replace that cable anyways but this problem always seemed more like a ground problem than a positive power problem. Also when did you buy your replacement cable, because I called some dealerships a month or two back and they all told me that not a dealer in the midwest carries them anymore. I could make my own but I have never done that before. Lastly, where can I find the main ground to the drivetrain. I looked once before but I didn't have much luck. Thanks again

Workaholic:
I agree with you, all these symptoms seem to point to a faulty ground somewhere but I don't know which one. I have cleaned a lot of grounds already trying to solve this. I took a dremel and cleaned and greased every ground that connected to the inside of the engine compartment and fenders including the intake manifold ground. Then found and cleaned the ground way in the rear of the truck by the bumper for what I thought was for the brake lights. I have found that the ground on the engine block that comes directly from the negative terminal of the battery is very very very rusty but I can't get to it to clean it off. Does anyone know how I could get to it easily? If I remember correctly its between the block and the vacuum pump or some other pulley. But I don't know of any other grounds. Are there any major ones that I'm missing including wherever the drivetrain ground is because I was not able to find it.

Thanks a ton guys. I really need to be able to count on this truck considering this is my only vehicle and have nothing else to drive to work or school.

 

Listen, I don't mean to scare you, but it "hain't cool messin' wit da devil". If it is the main ground, and you just cleaned up all the auxillary grounds, you may have created a potentially hazardous or destructive scenario. If you need me to, I can explain later about high voltage seeking the path of least resistance and the damage it can cause. But, in the meantime, I wouldn't start the truck untill you at least install some type of temporary heavy duty ground from battery - to the block.

 

My starter cable was only like 20 bucks at Napa Auto Parts CBL 718036 napas part number exacly the same as ours just less guage. As for the ground i just got a universal 72 inch i belive and ran to the driveline Battery to fender to trans to engine bolt) sure sounds like your Alt is tossing out more than 14 volts...... I forgot to say i replaced my ground cable up there^ Good luck!

 

And I'd like to stay as far away from the devil as I can. I understand that electricity runs through the easiest path but what are you supposing this destructive scenario could be?

 

And thanks for that part number. That is a super huge help and made my life a ton easier. I really appreciate it. When I searched this part on the napa website the positive and negative cable came up. Did you use this ground cable from napa or did you just buy wire and run it around the truck yourself, because the way you said you ran your new ground doesn't sound like it's the same as my factory one is.

 

The evil ground path sneaks its dirty little seeking tendancies wherever the easiest path is. Usually the exhaust somewhere. If you have all rubber hangers, it could go to the brake lines, or even fuel lines. It's not common but I've worked at a starter alternator shop for 30+ years and trust me it DOES happen. However rare any electrical scenario may be, your safety is most important, and when I read your thread, I became concerned so I felt compelled to just warn you, but not scare you, because I think this is a great little forum and I love my old Ford truck too (usually).

 

hmmm... that never crossed my mind. I guess it could become quite a fireworks show. thanks for the warning. And ohhhh yeah I hear ya on the "I love my old Ford truck too (usually)." I'm going to fix it as soon as I figure out how disconnect my old ground wire and I might borrow one of my Parent's car in the meantime. Thanks for the tip. While we're at it, anybody know how the old ground comes off? Looks like there's a bolt in the block that holds it on but then it's connected to the frame between the battery and block and i cant figure out how it's connected there.

 

I ran a universal 2 post ground cable zip tied following the old ground cable to the block left the old cable in place maybe someday ill get to that. So one wire from - terminal to fender and the thicker guage just route along the old ground and install to block making sure all the areas are nice and clean! Should I hope fix your problem let us know!

 

A couple thoughts.
Both of my 1995 f150 351 (as well as 2 previous 1992 f150 with 302)when idling the. Volt gauge drops a bit, if I tap the gas or rev the truck then it goes back to normal. So I think it's a normal thing. If I turned the headlights and heater off then the gauge would be normal a idle. (mind you I haven't seen one bounce around like yours

The random starting issue. If you look on your started there is a spade terminal, just a single wire I believe. I bet that's loose or corroded. Mine had the issue where there would be a clunk and nothing else when the key is turned. I'd wiggle the wire and I would start right up. I ended up squeezing the connector a little so it got better grip on the terminal

 

Here's a vid of mine. My gauge doesn't bounce around like yours tho
http://www.youtube.com/watch?v=BtsEL...e_gdata_player

 

wow that's exactly what mine does usually when it's not bouncing crazily like in the video. I guess it must be normal or at least popular for our trucks. Thanks for taking the time to make the video. Now I can rule that symptom out About that spade terminal though, I have heard that before and mine has seemed fine. And say that spade terminal was my problem... i'm almost positive that it being loose would not cause me to loose power completely to everything in my truck or cause the voltmeter to bounce like that.

Thanks again

Hey Donniezyea,
did you use the bolt in the block that the old ground used to connect the new ground? And here is my real dilemma. If you follow the ground real carefully it connects to the frame on it's way to the block. I have no freaking clue how it is connected there. Its a hard spot to find but it doesn't look like it's clipped or bolted but it's stuck to the frame pretty good, definitely intentional.

 

FIXED

so far... I got around to installing new positive and negative cables off the battery a couple days ago and so far its been great. Although my problem was very random before i am almost sure this fixed it for good. Thanks to you all for your help.

In conclusion, anyone who may be reading this and experiencing similar symptoms it is probably your ground cable from personal experience. Bought my parts at Napa using the part number given to me by a good samaritan above, and it really wasn't too tough of a job.