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  • 1974 - 1978 Mustang II Talk & Tech

question(s)...

  • Thread starter Thread starter fourone3
  • Start date Start date Sep 25, 2004

fourone3

New Member
Jul 18, 2004
27
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Western Mass
Sep 25, 2004
#1
  • Sep 25, 2004
  • #1
I'm sure I've gone unnoticed here lately... but I haven't been on because I've been working on my car to get it running right. Perhaps you could be of help...

So the lights and everything else electrical have been acting really weird lately... they flicker and whatnot. The temp. gauge also goes up whenever the lights or brakes are on, so I got freaked out at first thinking it was getting really hot. But that's not the worst... the car won't start at random... I replaced the battery, the starter relay, and the alternator... it's still doing it. Any thoughts on this crazy thing?

Also, how do I put up a picture under my name and get a picture of my car somewhere on here?
 
C

COBRAIIW

New Member
Apr 26, 2003
562
1
0
CT
Sep 25, 2004
#2
  • Sep 25, 2004
  • #2
Here we go again! Check ALL your grounds. There is a strap that goes from the back of the block,(or head on the pass. side) to the firewall.It should be making clean metal to metal contact at both ends.
Also check the grounds from the instrument cluster to the instrument panel support bracket.
Remember,corrosion is the ENEMY!
 

Mstng2

Founding Member
Jun 27, 2002
789
5
19
- - Zion - -
Sep 26, 2004
#3
  • Sep 26, 2004
  • #3
ok, so ground wires, then on the other stuff to put an Avatar by your name go to user CP up top of the forum page and edit your profile. The pic has to be small thumbnail size 32k or less or less than 90X90 pixels. To post pics within the forum you have to be able to have your pictures hosted by a different web-site. Most Internet services have webspace included with your subscription. Just ask them how to post a webpage. Then when you post a message just click on the little icon with the mountian and put in the address of the picture. And WALA it shows up in the post.
 

fourone3

New Member
Jul 18, 2004
27
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0
Western Mass
Sep 27, 2004
#4
  • Sep 27, 2004
  • #4
Sorry about that. I'm just a little frustrated at this thing. I did check that cable to the firewall and cleaned around it with a wire brush. I'll check again and replace it if I have to.

Thanks for the know-how on this and the avatar.
 

Mstng2

Founding Member
Jun 27, 2002
789
5
19
- - Zion - -
Sep 27, 2004
#5
  • Sep 27, 2004
  • #5
Check your headlight harness grounds too. they go from the headlight harness to the radiator support. There is also one from the heater blower motor to the firewall. Any others? Anyone?
 
Z

zwhitr

Founding Member
Aug 26, 2001
847
0
16
Goldsboro, NC
Sep 27, 2004
#6
  • Sep 27, 2004
  • #6
fourone3 said:
I'm sure I've gone unnoticed here lately... but I haven't been on because I've been working on my car to get it running right. Perhaps you could be of help...

So the lights and everything else electrical have been acting really weird lately... they flicker and whatnot. The temp. gauge also goes up whenever the lights or brakes are on, so I got freaked out at first thinking it was getting really hot. But that's not the worst... the car won't start at random... I replaced the battery, the starter relay, and the alternator... it's still doing it. Any thoughts on this crazy thing?

Also, how do I put up a picture under my name and get a picture of my car somewhere on here?
Click to expand...


well good luck on the car I think if I got off the darn computer I would have more time to work on the car mine runs just trying to purdy it up.

when you say it won't start do you mean it wound turn over or wont fire up

might be a bad switch --mounts on the steering column
neutral safety switch

can you jump the solenoid [actually just apply power to the center electrode]


are you getting good spark --coil, ignition box,


Try to be more specific so we can better help you.
 

fourone3

New Member
Jul 18, 2004
27
0
0
Western Mass
Oct 1, 2004
#7
  • Oct 1, 2004
  • #7
I'll try and start it and it'll do absolutely nothing; as if the battery is dead or not connected. I could try it again a few more times and it'll start, but other times I'd leave it for days and then it would start right away. When it does start and I drive, the temp. gauge goes up when I put on the brakes, lights or radio. The lights dim and flicker and the radio will turn off when I put on the brakes, turn on the lights and sometimes when I put on a blinker. The lights also get brighter when I put on the gas.

I replaced the plugs and wires at the beginning of the summer, but didn't really look at the coil or box. Can I check those for problems, or just replace them?
 
C

cilynx

New Member
Jun 12, 2002
19
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0
Milwaukee, WI
Oct 1, 2004
#8
  • Oct 1, 2004
  • #8
I've had mine do the every now and then just not trying to start. Once it was the electronic ignition box dying, the other time it was the neutral safety switch. With the neutral switch, if I ran the shifter back and forth a couple of times, it would always start.
 
L

LedZ 5.0

now you have my pea brain going in circles
Apr 1, 2004
204
0
0
Oct 2, 2004
#9
  • Oct 2, 2004
  • #9
fourone3 said:
I'll try and start it and it'll do absolutely nothing; as if the battery is dead or not connected. I could try it again a few more times and it'll start, but other times I'd leave it for days and then it would start right away. When it does start and I drive, the temp. gauge goes up when I put on the brakes, lights or radio. The lights dim and flicker and the radio will turn off when I put on the brakes, turn on the lights and sometimes when I put on a blinker. The lights also get brighter when I put on the gas.

I replaced the plugs and wires at the beginning of the summer, but didn't really look at the coil or box. Can I check those for problems, or just replace them?
Click to expand...

Since the car wants to start sometimes and not at other times the problem could be the ignition module or wiring connections to the module.

Could be your alternator is not putting out enough amps to keep the accesories working. Check the regulator and wiring connections on the drivers firewall and remove the alternator to have it tested at Auto zone or a local rebuild shop.
 
T

THE COBRAMAN

pig 'rassler
Founding Member
Mar 11, 1999
1,974
0
36
Oklahoma
Oct 2, 2004
#10
  • Oct 2, 2004
  • #10
For the not cranking: Check the starter relay. It grounds through the mounting ears. It is attached with sheetmetal screws and they are often stripped, causing poor grounding.

For zwhitr: FWIW, the neutral safety switch is on the trans case around the shift shaft on every floor-shift automatic Ford I've ever seen.

When you say you checked the ground to the firewall, was it the battery ground, or the small non-A/C blower motor ground? The original setup for 302 cars had the battery to chassis ground made on as part of the negative cable ( a tab that was soldered/crimped onto an uninsulated portion of the cable) which was then screwed to the firewall below the cowl pinchweld. Most people do not replace that ground when changing battery cables, and it will cause exactly the flickering, etc that you have described.
 
Z

zwhitr

Founding Member
Aug 26, 2001
847
0
16
Goldsboro, NC
Oct 2, 2004
#11
  • Oct 2, 2004
  • #11
cobraman said:
For zwhitr: FWIW, the neutral safety switch is on the trans case around the shift shaft on every floor-shift automatic Ford I've ever seen.
Click to expand...


zwhitr said:
might be a bad switch --mounts on the steering column
neutral safety switch
Click to expand...


Right Cobraman I was referring to the actual switch block that mounts on the column may be bad

then I was listing the neutral safety as another culprit

Sorry for any confusion that may have caused
 

fourone3

New Member
Jul 18, 2004
27
0
0
Western Mass
Oct 4, 2004
#12
  • Oct 4, 2004
  • #12
THE COBRAMAN said:
When you say you checked the ground to the firewall, was it the battery ground, or the small non-A/C blower motor ground? The original setup for 302 cars had the battery to chassis ground made on as part of the negative cable ( a tab that was soldered/crimped onto an uninsulated portion of the cable) which was then screwed to the firewall below the cowl pinchweld. Most people do not replace that ground when changing battery cables, and it will cause exactly the flickering, etc that you have described.
Click to expand...

I did replace the relay first since that has been a problem with me before. I'll double check the way it's attached though. I checked for the battery to the firewall. But after looking at it again, it's a very small gauge. If I had to guess it's a 14 or 16. Does that matter, or should I find one that's a bit bigger? I used the wire that was on there, so I think I'll get a new one since it isn't exactly in the best condition.

I also replaced the alternator a week ago and the ignition module about 2 years ago. Do they go bad that quickly?

ZWHITR, when you say the neutral safety switch, that's the switch that makes it so you have to start it with the clutch depressed?
 
Z

zwhitr

Founding Member
Aug 26, 2001
847
0
16
Goldsboro, NC
Oct 6, 2004
#13
  • Oct 6, 2004
  • #13
fourone3 said:
ZWHITR, when you say the neutral safety switch, that's the switch that makes it so you have to start it with the clutch depressed?
Click to expand...


no ----Neutral safety switch = car must be in Neutral/Park to start auto's only

not sure how the clutch switch is wired in.

what year did they start that?
 
M

mustang2

New Member
Apr 29, 2004
212
0
0
NC
Oct 6, 2004
#14
  • Oct 6, 2004
  • #14
In reference to the ground that goes from the firewall to back of head.
On mine the battery ground goes to an intake bolt and there is nothing going from the firewall to block or head.
Is it okay if I leave the battery ground going to the intake, and then get a ground strap to put between the firewall and head?
 

itsaMustangtoo

New Member
Apr 2, 2005
292
0
0
Carlisle,Pa
Apr 13, 2005
#15
  • Apr 13, 2005
  • #15
I do not feel as though you have a ground problem.As far as the lights getting brighter as you rev the engine,that could be a weak alt. or more likely resistance in an old wiring harness. My 74 did this but I had a bunch of splices in it from modifying the harness.Now for the real problem ( the gremlins ) In the engine compartment,take the bolt out of the harness( where it goes through the firewall) to the fuse block. Take a good look for corrosion,clean good, and put back together. I will bet this solves your problems. Also do not tighten the bolt too hard when you put her back together, the fuseblock will crack and never stay tight. GOOD LUCK
 
C

COBRAIIW

New Member
Apr 26, 2003
562
1
0
CT
Apr 13, 2005
#16
  • Apr 13, 2005
  • #16
read the date of mustang2's reply.
 
M

mustang2

New Member
Apr 29, 2004
212
0
0
NC
Apr 13, 2005
#17
  • Apr 13, 2005
  • #17
And to answer our own question back then when we were young and un-knowing. We did put a ground strap from the firewall to the intake, and then a ground cable from the intake to the battery.
We have no idea if it works yet, because the car has'nt moved.
 
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