Fox Do I have a bad ground? Intermittent starting/electrical issue (93 GT)

JCBeaver

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Mar 23, 2018
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Hello everybody,

I am trying to get to bottom of my intermittent starting issue. The electricals sometimes will go 100% dead when I hit the RUN/START position. Often, I would have to toggle key back and forth and then it will finally keep 12V and crank the engine. See attached video of what I did yesterday to show the issue. This problem is present from time to time, but not every time.

48637463302_51f409262d.jpg
IMG_1063

*click on image above to activate video showing my problem*

When I have this issue present, everything always lights up and everything gets 12V no problem when I put the key into ON position, but once I hit RUN/START, the power disappears.

I am wondering if you guys could tell me if I do, indeed, have a bad ground going to the block, not supplying enough grounding to the starter/engine?

Only happens when I hit START position, which leads me to think that I have a bad ground on the block/ to the starter so thats why it is only happening at RUN position. I need to use the voltmeter to watch how the voltage acts when I am cranking the engine. Assuming if I see too much of a drop below 10V then I probably have a bad ground on the block?

I should note that I did paint the block with engine enamel. I painted it in a few coats. I did sand down the ground cable point on the back of the block and on side of the block, but I am beginning to think I might need to sand down the starter mounting points. I probably will add another ground strap between the block and the body just to provide the engine another block to body grounding point.

Any input will be appreciated! Thanks!

Pictures for attention (just buttoned up my new KB 2.1L Blowzilla, need to get the tune done) :

48637018113_3c6977730c.jpg


48637023743_571087d8a9.jpg


Have a good day, everyone!

-Jarvis
 
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90sickfox

I didn't really have an issue with the stink...
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It never hurts to add a ground cable from the lower starter bolt to the k member or bottom engine mount bolts. Can't have too many grounds.

It sounds to me like you have an issue with the ignition electrical switch on the column. Very common issue on foxes.

Usually, a bad ground will cause the starter to click but not turn the starter motor. Unless there is absolutely no ground at all.... in the later case you'd get diddly squat.
 

JCBeaver

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Mar 23, 2018
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It never hurts to add a ground cable from the lower starter bolt to the k member or bottom engine mount bolts. Can't have too many grounds.

It sounds to me like you have an issue with the ignition electrical switch on the column. Very common issue on foxes.

Usually, a bad ground will cause the starter to click but not turn the starter motor. Unless there is absolutely no ground at all.... in the later case you'd get diddly squat.
Good idea. I can try adding that cable from the starter bolt to the k member. I recently went into the garage to see what my voltage is like when cranking. It seems to go down to 10.XX volts while cranking (when it does crank). Seems to be normal so I am not sure if I have a bad ground anymore.

You are probably right on the ignition switch. Thinking about it, this problem kind of started sometime after I replaced the switch just for heck of it when I was chasing a separate no start issue last Spring. Turns out my problem was elsewhere, not the ignition switch and then this started to happen.... Hmm, you got me thinking... Is there any way I could "test" for this kind of thing? Once again it is intermittent so I am unable to make this problem come back when I want it to LOL.

Also another note I wanted to make: Car shut off on me on the highway other weekend... Out of blue it just shut off while I was cruising on the fast lane.. Pulled over and it wouldnt crank again for like 20 minutes before it finally cranked. Went back on the road no problem. Same thing happened once before I moved out to CA last Spring... On that occassion, I had to wait 30 mins before the car would crank again. Seems to do that when the car is warm/hot..
 

JCBeaver

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I also have dead red/yellow wire that provides 12V to my gauge cluster, coolant sensor, etc which is part of the VPWR circuit. One day last spring, they all stopped supplying power for some reason I cant figure out. If my memory serves me right, this issue came up at around the same time I started to see this intermittent starting problem. Not sure if it is just a coincidence or they are actually related. Just wanted to throw that out there.
 

JCBeaver

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Thanks, but with my limited knowledge I am not sure where to start at. And I cannot stimulate this electrical issue in RUN position every time. It just comes and goes.

For the VPWR wiring. I just don’t see 12V at certain VPWR ends but can’t figure out why those certain ones aren’t getting 12V while other ends on this circuit do have 12V. (MAF 12V is still intact)
 
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JCBeaver

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Sorry reading on the phone while driving is a bad idea. I didnt see you pointed out the fuse #18.. Thats the first time I saw that certain diagram you just attached. Let me check on that fuse #18.
 

JCBeaver

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I'll be damned. You are correct the Fuse #18 was blown and now I have 12V at low coolant level sensor again! Thank you!

I also had dead R/Y 12V Input wires at the instrument cluster connectors on both sides. After looking at that instrument cluster diagram you attached. It appears all of those wires are connected to fuse path #18.

I could test them out but they are behind my cluster bezel and I am feeling lazy haha. I am positive I can cross this issue off my list!

Guess my intermittent starting is an independent problem. Not related to this wiring problem.

EDIT: I answered my own question so I altered the post accordingly
 

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General karthief

wonder how much it would cost to ship you a pair
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There is a ground wire that attaches to the driver side head at the back and then to the firewall, I see you have upgraded the alternator, did you upgrade that wire too?
start at the battery and clean all the connections, both + and -.
I agree the the symptoms point to the ignition switch.
 
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JCBeaver

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I apologize. I realized I have been saying the power goes out when I hit RUN position when I
There is a ground wire that attaches to the driver side head at the back and then to the firewall, I see you have upgraded the alternator, did you upgrade that wire too?
start at the battery and clean all the connections, both + and -.
I agree the the symptoms point to the ignition switch.
Good point.

I have 0 gauge ground cable from battery to side of the front timing cover, 4 gauge battery pigtail to body, stock ground strap on rear of the drivers side head to the firewall.

Now you got me thinking I need to beef up the ground behind there to at least 4 gauge. Not sure if I have a room to work on that grounding point, but I will try.

I also need to clean the battery connectors just to be sure. My terminal clamps are some chinese crap so maybe they are suspect.

I bought this ignition switch I am currently using from Advance Auto on 4/12/19 so I am going to take it off and bring it to the store to get a free replacement just to see if it helps any.
 
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