Wiring Issue with 1986 C4
Thread Starter
2nd Gear
Joined: Aug 2022
Posts: 2
Likes: 0
Wiring Issue with 1986 C4
My 1986 Corvette does not want to start...acts like no power when I turn the key. Occasionally if I move the battery cables(cables are tight) I can get the dash and interior lights to come on but still not enough juice to start it just clicks(battery is new). I do not see anything obvious as far as lose wires etc But I do have a single red wire (maybe 18- 20 gauge not heavy current wire)that comes through the firewall directly behind where the battery would sit that goes nowhere its approx 6 inches long. The car has no aftermarket items(radio etc) so not clear if this was a an aftermarket add on or part of factory wiring. I did not want to connect this to the battery for fear of damaging some of the electronics without knowing what this wire may supply to the electronics. Any ideas would be appreciated...do other 1986 have this wire and if so where or what should it connect to...Thanks.
Pro
Joined: Oct 2000
Posts: 616
Likes: 118
From: Alpharetta GA
Definitely sounds like a loose connection. Start tracing the battery cables and make sure they are tight.
The LegitStreetCars YouTube channel just did a video on an 87 Mustang GT where the ignition was acting wonky and wouldn't keep the car running. They found the connector in the steering column was loose. Initial "fix" was using a ziptie to keep the ignition connector fully seated. Once they got the car fully running, they ordered a new ignition connector.
The LegitStreetCars YouTube channel just did a video on an 87 Mustang GT where the ignition was acting wonky and wouldn't keep the car running. They found the connector in the steering column was loose. Initial "fix" was using a ziptie to keep the ignition connector fully seated. Once they got the car fully running, they ordered a new ignition connector.
Team Owner
Joined: Sep 2003
Posts: 25,413
Likes: 2,745
The 'RED" is for sure an add of sorts but who might know why or what? An attempt to bypass the ignition and get 'crank & run'?
Do you have yet the FSM (Factory Service Manual) for your car? If you don't you for sure need it and what ever you consider you need to be sure it has the EDM (Electrical Diagnostic Manual).
I can provide you with the FSM including the EDM in .pdf for a similar price as eBay or others, often less. I also provide when you buy from me a GM SPO Parts Catalog that would certainly aid in parts research for your car. I cant PM you yet BUT if you click on my 'User ID' to the left you'll be given an option to PM or email me. Drop me an email and I'll explain. Many have my FSM.
Do you have yet the FSM (Factory Service Manual) for your car? If you don't you for sure need it and what ever you consider you need to be sure it has the EDM (Electrical Diagnostic Manual).
I can provide you with the FSM including the EDM in .pdf for a similar price as eBay or others, often less. I also provide when you buy from me a GM SPO Parts Catalog that would certainly aid in parts research for your car. I cant PM you yet BUT if you click on my 'User ID' to the left you'll be given an option to PM or email me. Drop me an email and I'll explain. Many have my FSM.
Thread Starter
2nd Gear
Joined: Aug 2022
Posts: 2
Likes: 0
Hi,
I do have a factory manual ...will try to see if some troubleshooting hints. I was hoping if someone had an 1986 they could advise on that red wire going through the fire wall whether or not anyone else had this on their c4 and what is the possible usage...like I stated there is not aftermarket devices(stock radio etc) on the car so do not know why anyone would be adding a circuit and not the easiest car to trace wires under the dashboard..
I do have a factory manual ...will try to see if some troubleshooting hints. I was hoping if someone had an 1986 they could advise on that red wire going through the fire wall whether or not anyone else had this on their c4 and what is the possible usage...like I stated there is not aftermarket devices(stock radio etc) on the car so do not know why anyone would be adding a circuit and not the easiest car to trace wires under the dashboard..
Team Owner
Joined: Sep 2003
Posts: 25,413
Likes: 2,745
Hi,
I do have a factory manual ...will try to see if some troubleshooting hints. I was hoping if someone had an 1986 they could advise on that red wire going through the fire wall whether or not anyone else had this on their c4 and what is the possible usage...like I stated there is not aftermarket devices(stock radio etc) on the car so do not know why anyone would be adding a circuit and not the easiest car to trace wires under the dashboard..
I do have a factory manual ...will try to see if some troubleshooting hints. I was hoping if someone had an 1986 they could advise on that red wire going through the fire wall whether or not anyone else had this on their c4 and what is the possible usage...like I stated there is not aftermarket devices(stock radio etc) on the car so do not know why anyone would be adding a circuit and not the easiest car to trace wires under the dashboard..
Racer
Joined: Aug 2021
Posts: 321
Likes: 44
Cable ends are original, not replacements that bolt on ? Change the battery cables. Check where each attaches to the car for any corrosion or loose connections. Do the simple stuff first. The fact that messing with the cables causes something to happen means I’d start there.
