Just completed the interior on my 1976, looks great everything new. Backed it out of the garage and could smell what appears to be burning wires. Anyone have any ideas on where to start versus tearing everything back out? Thanks

 

Not sure if this would work but try a battery operated smoke detector and move it around under the dash and other areas of where you suspect the smell might originate.

 

Thanks, never thought of that. Might help get me in the right area. For some reason I'm thinking the cig lighter may have something to do with it. As my AIM and Repair Manual go to great extent on the importance of the ground for that wire. Numerous assorted washers in specific order. I thought I had it all right but something makes me think this could be the culprit. Thanks again for the recommendation, I will give it a try.

 

If you don't have any visible smoke then the smoke detector will not likely trip. The detector needs at least a trace amount of smoke drawn into the chamber to be able to sense it. I would close up the windows and top and see if the smell is strong inside. I would put a disconnect switch on the battery in case things start burning and you need to cut power in a hurry.

 

The smell is definitely in the inside, had all the windows up and tops on, hood open, no smell under the hood, sting smell inside. I could not see any smoke at all, but definitely smelled like burning wires and the longer I left it running, the stronger the smell got. I left it outside for about 3 hours, got in and no smell, started it up long enough to move it back in the garage and shut it right off, no smell, so it appears to get worst the longer it runs.

 

Might have a pinched wire under the dash, or a screw cut into the wire. Easy to do, finding it not so easy. I would leave it outside, or make sure battery is disconnected. A car fire in the garage is not pretty. Are any of your lights dim, radio and speakers work, turn signals? Finding a part not working correctly or a hot fuse, might help locate problem. I have seen lots of wire pinched around area of steering colum. Look for pinched wires under bolts for seats if they are power seats and you removed them. Do visual inspection first.

 

NOT IMPLYING THIS TO YOU OR ANYONE here on the forum.

I have dealt with more screwed up electrical problems and some actually came into my shop AFTER there was an electrical fire.

What DO is I go right to the source of where the current gets distributed. Usually the wires at the starter solenoid have had the fusible links removed and by-passed....which basically means the car is NOT protected in regards to this constant battery power....which goes to your IGNITION SWITCH and headlight switch.

NOW the fuse panel is going to protect any outgoing power to whatever item that teh fuse is protecting.

Chances that you pinched a wire would not cause for this issue.....UNLESS the amp load that the wire you pinched is so great that it is building up resistance in the wire and causing it to get hot and stink. IF the wire got pinched so much that it contacted a metal part of the car...the fuse would pop.

SO a lot of it depends on what you have ON when you smell the burning wire smell.

DUE to the smell going away when you turn off the car...it is SAFE to assume that the problem deals with a circuit that only get 12 volts when the key is on. SO all circuits that are HOT (12 volts) when the key is out of the ignition and OFF are NOT the problem. IF they were...the smell would be there ALL the time. I cannot grasp it that this smell would only occur if the engine is running...so you can test it with just the key ON and the engine NOT running.

DUB

 

You can turn on various electrical circuits WITHOUT starting the engine. So, turn the ignition key to the ON position...with most of the electrical devices turned OFF...and just sit and see if you get the same smell as when the vehicle is running. If not, then start turning ON the various electrical circuits, one at a time, and doing the same thing (lights, wipers, radio, etc, etc.). If you go through all those items and you still don't have the burning wire smell, you might consider that it could be the result of some action you did during your work (something newly painted getting hot and giving off odor, etc.).

When you encounter the smell, follow your nose. Really move your head around the passenger compartment and sniff carefully, comparing results to point your toward the source. Also, open the hood and check for the same smell there. If you still can't find it, and you still believe that it is electrical in nature, you should keep diagnosing the problem until you find it. If you get frustrated and just drive it normally, you might end up with a very costly fire situation.

 

Anything new or moved around the exhaust under the car? Just throwing it out there because you said it gets worse the longer it's running and it takes the pipes under the car a bit to get hot enough to burn plastic.

 

Nothing has been touched under the car. I was wondering, when I did the interior, I put heat barrier on the floor pans and transmission tunnel and used 3M adhesive to keep it in place, any chance this is getting hot and the glue or material is melting? I pilled the center console side panels and shift plate cover last night, no sign of any melting wires. Also inspected under the dash and fuse box, again, nothing looks like it is melting and all looks normal.

 

The interior looks great anyway

 

I used the 3M spray adhesive to hold heat barrier stuff in place and I did not detect any 'burning wire' smell as a result. If you used a different type of 3M adhesive, odor from getting it hot prior to fully curing could be an issue.

I think the tests to determine if the operation of electrical equipment would cause the smell without starting the engine would be your best bet. You need to isolate WHEN and WHERE the smell is eminating.

 

7T1vette, I'm going to test that process tonight. Hopefully, it reveals the source. Thanks

 

I was 'thinking'...and it is not that much of a stretch. BUT...if a light bulbs is lit up...and is touching something plastic....it will get hot and smell.

I would possibly look at the light bulb for your AC/heater controls in the console. IF it fell out and is resting on something that can get hot and smell. Making sure the floor board interior lights are not on and or near something plastic.

I have got nothing else until your tests come back with more info where you can localize the smell.

DUB

 

Pulled the gauge cluster, radio, shift plate and parking brake console to expose the majority of wiring. I did not see any wires that may have been pinched or punctured by a screw. Turned the key on without starting the car for about 5 minutes and did not smell anything. I'm going to start the car tonight with everything exposed to see if I can pinpoint where the smell is coming from. However, reading through all the replies, I remembered that after removing all the interior, I had to replace the drivers side floor pan due to rust, had a body shop replace the floor pan and after installation they painted it. I drove it home after they did the work, only about 5 miles in the rain and did not smell anything, but the car had not been started since and everything is dry. Could it be the paint is now dry and heating up?

 

YES...depending on what they used...it can be curing and out-gassing vapors.

DUB

 

I have had 3 car electrical fires. The first in a 73 malibu, (wish I still had that one...$h!%)...the power wire to the stereo rubbed through to ground near the fuse box in the passenger compartment.

The second was on an 87 Shelby Charger (fast, fast turbo car...high 11 sec 1/4)...a wire rubbed through (don't remember which one) in the engine compartment. That car made a lot of people angry, if you know what I mean and I still have a grin when I think about that car.

And the third fire. 91 Toyota pickup. Power wire to the stereo amp pinched when I put the seat back from getting stuff from behind the seat.

3 fires...Didn't lose one of them. Got lucky.

 

Be careful with wiring. I had something I discovered just yesterday. This was not on the Vette but could happen in any car. I bought the Cobra knowing the passenger side fan was not working. Thought something easy like a fuse or relay. Taking the dash apart revealed all the wiring so I tried relays and still nothing. I put direct power to the fan and it worked. So started taking voltage at different point. Found the main power feed had 12 volts at the source but only 6.2 at the relay. Looked at the fuse holder and all the wiring looked perfect. Figured it had to be the wire had some resistance. It had a few soldered joints for the fuse holder and one going out to the fan. Not wanting any problems I ordered a new seal harness. After pulling the old one out I started to dissect the harness. After pulling the perfect looking shrink tube off this is what I found. So even though it looks good it can be burnt or charred. This wiring was not old either like most of our 40+ year old cars that were not designed to carry the amps we are putting in there now.

 

With the gauge cluster, shift plate, parking brake console and radio removed, I started the car and pulled it out of the garage, same scenario as the first time I smelled the burning wires, everything off except for the heater, just as before. Now, no burning wire smell. I let the car run for 30 minutes and could not get it to make that same smell (which is a good thing). Tested all the fuses, everything is good. checked all the lights, wipers, heater fan speeds, power windows and all is good. So now I think maybe something was pinched and when I removed everything it unpinched the wire, therefore no smell. I pulled the car back into the garage and shut it down. Them proceeded to attempt to closely inspect each of the 100's of wires in and around the underside of the dash. I did find that the wire to the light for the ashtray compartment had a bare spot and wires were exposed. I could find nothing else. I taped the wire up and will try to neatly gather all the wires and secure them, than re-install all the components back into the car and see what happens. Thank you to everyone that posted. Great ideas, great feedback and definitely provided me some knowledge. I will let you know how it turns out.

 

Hope you fixed it, might never know what it was that caused it. I was also thinking about the blower motor. You might have stirred up A lot of dust and the dust burning off he blower motor could cause the odor too. The interior sure does look good, nice work. More pictures.