My 94 electrical issue - MustangForums.com



5.0L (1979-1995) Mustang Technical discussions on 5.0 Liter Mustangs within. This does not include the 5.0 from the 2011 Mustang GT. That information is in the 2005-1011 section.
Sponsored by:
Sponsored by:

Reply
 
 
 
Thread Tools Search this Thread
Old 10-23-2017, 12:28 AM   #1
MustangGTJunkie
Thread Starter
 
Join Date: Oct 2017
Location: South Carolina
Posts: 2
Default My 94 electrical issue

I gotta 94 gt 5.0ho ohv. Its my dd and the temp gauge starting maxing out and then the oil pressure gauge did the same thing but it never actually started running hot but i replaced the thermostat amd the radiator and that wasnt it. So does anybody know what is? I was told it was probably a grounding issue. What does that mean ? Im new to this.
MustangGTJunkie is offline   Reply With Quote
Old 10-23-2017, 01:40 AM   #2
imp
2nd Gear Member
 
imp's Avatar
 
Join Date: Jul 2017
Location: AZ
Posts: 244
Default

Quote:
Originally Posted by MustangGTJunkie View Post
I gotta 94 gt 5.0ho ohv. Its my dd and the temp gauge starting maxing out and then the oil pressure gauge did the same thing but it never actually started running hot but i replaced the thermostat amd the radiator and that wasnt it. So does anybody know what is? I was told it was probably a grounding issue. What does that mean ? Im new to this.
Two gauges acting up at the same time suggests something wrong with other than the gauges themselves, rather a poor ground connection causing incorrect response. Give me a bit of time to check my wiring diagrams to try to direct you in an appropriate direction. I, too, drive a '94 GT. Try to get back tomorrow. imp
imp is offline   Reply With Quote
Old 10-23-2017, 10:50 AM   #3
MustangGTJunkie
Thread Starter
 
Join Date: Oct 2017
Location: South Carolina
Posts: 2
Default

Quote:
Originally Posted by imp View Post
Two gauges acting up at the same time suggests something wrong with other than the gauges themselves, rather a poor ground connection causing incorrect response. Give me a bit of time to check my wiring diagrams to try to direct you in an appropriate direction. I, too, drive a '94 GT. Try to get back tomorrow. imp
Cool that would help out alot. The electrical stuff just isnt my specialty ha
MustangGTJunkie is offline   Reply With Quote
Old 10-23-2017, 11:22 PM   #4
imp
2nd Gear Member
 
imp's Avatar
 
Join Date: Jul 2017
Location: AZ
Posts: 244
Default

Quote:
Originally Posted by MustangGTJunkie View Post
Cool that would help out alot. The electrical stuff just isnt my specialty ha
If it is caused by a bad ground connection, affecting Temp. and Oil Pressure gauges, those both are grounded externally of the instrument cluster. Unfortunately, the wiring diagrams do not show physically WHERE this ground connection is located. My guess is it's behind the instrument panel, possibly grounded to the sheet metal frame of the dashboard. It will be close to the instrument cluster, and behind or beside it. Getting to that location would likely be easiest by removing the cluster and bringing it outward towards the steering wheel. The grounded wire will be colored BLACK with a WHITE STRIPE, and have a lug on the end where it is screwed to the body structure. FWIW, the conductor number is 397, in case you find someone with more detailed wiring location information.


Good luck! imp
imp is offline   Reply With Quote
Old 10-24-2017, 10:02 PM   #5
wbrockstar
 
wbrockstar's Avatar
 
Join Date: Jul 2017
Location: Tn
Posts: 40
Default

Im not sure on the 94-95 models,but the secondary ground on the 86-93 Mustangs is located between the driver cylinder head (rear) and the firewall.Its a flat braided ground strap.This is the ground for the interior/exterior lights,ac clutch,alternator and the gauges.A sign of a bad ground at this location is a temp gauge increase once you turn things on like the ac,blower motor,headlights.If your ground strap is the original,it needs to be replaced,but for trouble shooting purposes,make sure its tight and corrosion free.Your problem is most likely this ground,but to check the gauges and wiring,remove the sender wire for each gauge and ground the wire to a clean spot on the engine block.The gauges should peg to full.If they do,that usually indicates the gauge and sender wire are good,which leaves the ground wire or sender as the possible cause.
wbrockstar is offline   Reply With Quote
Old 10-24-2017, 11:39 PM   #6
imp
2nd Gear Member
 
imp's Avatar
 
Join Date: Jul 2017
Location: AZ
Posts: 244
Default

Quote:
Originally Posted by wbrockstar View Post
Im not sure on the 94-95 models,but the secondary ground on the 86-93 Mustangs is located between the driver cylinder head (rear) and the firewall.Its a flat braided ground strap.This is the ground for the interior/exterior lights,ac clutch,alternator and the gauges.A sign of a bad ground at this location is a temp gauge increase once you turn things on like the ac,blower motor,headlights.If your ground strap is the original,it needs to be replaced,but for trouble shooting purposes,make sure its tight and corrosion free.Your problem is most likely this ground,but to check the gauges and wiring,remove the sender wire for each gauge and ground the wire to a clean spot on the engine block.The gauges should peg to full.If they do,that usually indicates the gauge and sender wire are good,which leaves the ground wire or sender as the possible cause.

Good Help! imp
imp is offline   Reply With Quote
Old 10-25-2017, 09:50 AM   #7
wbrockstar
 
wbrockstar's Avatar
 
Join Date: Jul 2017
Location: Tn
Posts: 40
Default

Apparently the 94-95 has a ground from the neg battery post to the driver side timing cover and another one from the driver side motor mount to the driver side framerail.
wbrockstar is offline   Reply With Quote
 
 
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Forum Jump

Advertising
Featured Sponsors
Vendor Directory

All times are GMT -5. The time now is 01:50 PM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.