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Weird Issue Going On, Need Help!

  • Thread starter Thread starter trng2build1
  • Start date Start date Oct 10, 2014
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trng2build1

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  • Oct 10, 2014
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I have a 91 mustang coupe. Just did head gasket job, then rebuilt the t5. Have the car running again now. But i have some new issues. I'll list them as follows:

1st) After getting the t5 back in the car and bolting up the exhaust, the car doesn't sound as loud st idle as it was before trans rebuild? Same exhaust as before i rebuilt the trans though. Ideas?

2nd) So I go for a drive tonight. Turn the headlights on and the passenger blinker is lit up? The dash lights are very dim. The blinkers don't work, don't know why. So i push the hazard switch to see if they work. Nope nothing, but the blinker light goes out and the dash lights get brighter (normal brightness for when headlights are on). So i turn off the hazard switch (lights get dim again) then turn on the blinker that's lit up, the dash lights go out, dash fuse blows (5 amp fuse). Anyone have an idea what the hell is going on? If you guys need pics of something lmk. I'll take some or upload a video to YouTube so you can see what is doing
 
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trng2build1

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  • Oct 10, 2014
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Update: so i uploaded a video to YouTube. The car did not blow the dash light fuse when i took the video. Maybe because the car want running? Here's the link to the video View: http://youtu.be/4PD4VuFYlMQ
 

Micheal Nadeau

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Oct 11, 2014
#3
  • Oct 11, 2014
  • #3
What happens when you unhook the flasher switch?
 
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trng2build1

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#4
  • Oct 11, 2014
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At work right now. I'll unplug it when i get home and see what happens
 
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trng2build1

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Micheal Nadeau said:
What happens when you unhook the flasher switch?
Click to expand...

By flasher switch, do you mean hazard switch?
 

Micheal Nadeau

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#6
  • Oct 11, 2014
  • #6
Yea
 
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trng2build1

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#7
  • Oct 11, 2014
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Doesn't get off till late tonight. Probably won't get to mess with it till Monday. Monday I'll take it off and see if that helps. Any suggestions about the exhaust?


Micheal Nadeau said:
Yea
Click to expand...
 

pearlnotchback

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Dec 18, 2011
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Oct 11, 2014
#8
  • Oct 11, 2014
  • #8
Check your ground wires
 

Micheal Nadeau

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Oct 12, 2014
#9
  • Oct 12, 2014
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The exhaust tone shouldn't have changed by just installing the transmission. Maybe lower idle, and it seems to not be as loud?
 
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trng2build1

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#10
  • Oct 13, 2014
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Micheal Nadeau said:
The exhaust tone shouldn't have changed by just installing the transmission. Maybe lower idle, and it seems to not be as loud?
Click to expand...

I drove the car a little and after pulling back up at the house the idle sounded quieter than when i first started it up.

pearlnotchback said:
Check your ground wires
Click to expand...

Where should i start checking? I know of a few ground locations (under ac area, near headlights..... but where should i look first?
 

jrichker

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There is a ground wire on the top of each side of the radiator support for the front lights. Make sure it isn't broken, corroded or missing.



 
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trng2build1

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Both those are good. What manual are the schematics from? Finding the grounds could be the issue. But knowing where inside the car to look for the grounds would be amazing
 

jrichker

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The diagram I posted is from the 92-93 Ford factory manual. I got it on CD, and it is somewhat awkward to use.

Try Googling for schematics and see what you come up with.

Helm Inc. has the OEM 91 Mustang manual but it's $90 and I am not sure that it includes the electrical diagrams,

http://www.helminc.com/helm/product...m=result&Style=helm&Sku=FPS1219391&itemtype=N
 
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trng2build1

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  • Oct 13, 2014
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jrichker said:
The diagram I posted is from the 92-93 Ford factory manual. I got it on CD, and it is somewhat awkward to use.

Try Googling for schematics and see what you come up with.

Helm Inc. has the OEM 91 Mustang manual but it's $90 and I am not sure that it includes the electrical diagrams,

http://www.helminc.com/helm/product2.asp?Make=FRD&Model=MUST&Year=1991&Category=1&class_2=FRD&mk=Ford&yr=1991&md=Mustang&dt=Shop/Service Information&module=&from=result&Style=helm&Sku=FPS1219391&itemtype=N
Click to expand...

Ok I'll try Google. Going to try to unplug the hazard switch and replace fuse and see if that changes anything. I know sometimes that the hazard switch can cause issues with the cluster illumination and what not. I'll post back once i do this and see if you can help me figure out the next step. Thanks for replying
 
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trng2build1

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#15
  • Oct 13, 2014
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Ok so, i unplugged the hazard switch. The passenger blinker light is no longer permanently on and cluster is correctly illuminating with it unplugged. The dash fuse did not pop either. Where is the ground for the hazard switch? I tried using a different switch, same result.
 
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trng2build1

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#16
  • Oct 13, 2014
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Also the blinkers still do not work
 

Micheal Nadeau

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#17
  • Oct 13, 2014
  • #17
The blinkers wont work with the hazard switch unplugged.
 

Micheal Nadeau

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Dec 30, 2013
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Oct 13, 2014
#18
  • Oct 13, 2014
  • #18
The white/light blue wire in the hazard switch runs back through the cluster, back to the multifunction switch, then to the right front light. Does the right front light work?
 
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trng2build1

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#19
  • Oct 13, 2014
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If you mean the headlight yes both work. Brake lights work reverse lights work
 

Micheal Nadeau

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Dec 30, 2013
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Oct 13, 2014
#20
  • Oct 13, 2014
  • #20
The exterior turn signal bulb
 
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