Electrical smoke inside the car

Hi,
I'm new here and would appreciate some help.
I've got a 1996 Disco 300TDi XS and was driving along the motorway the other day when I noticed smoke coming from behind the dash.
Having had the fright of my life, stopped at a fire station, driven home (more smoke) to change cars and then gone back to collect my family I then started to think about where the smoke had come from.

1st asumption, head unit. I installed it and took a feed for a road angel too. All removed, quick drive and still smoke!!!!

2nd assumption Fan controller. I can't replicate this at idle though. It only seems to smoke having been driven. When warm with the fan on (any setting it appears) the smoke starts, fan off - smoke stops. I've taken the fan resitor out but don't know what resistance I should see across each terminal. I've also not managed to find any charred wiring.

Am I in the right area? Has anyone else had this problem?
Since I've not really wanted to drive it the MOT has now expired as well.
Can anyone point me in the right direction?

Thanks in advance.
Gareth

All the standard electrical circuits are protected by a fuse for short circuit but any overheating can damage materials and set them alight before the fuse blows.
You say you can smell smoke when your driving ,so not when just running the engine running and the disco is stationary so I would look for the problem external to the cab.
But as it could be any electrical circuit who knows. Are you sure it's electrical not something like brakes?

I would turn on the ignition but NOT start the engine, and leave it for 20 mins or so, does it start to smoke? If not start the engine, and leave it to idle for a while, does it start to smoke now?

By doing this you can work out if it is indeed electrical or if only when the engine is running exhaust heat melting something etc...

If you cannot get it to smoke with the ignition on or engine running then it is a circuit related to driving, i.e. indicators or brake light circuits however these should be fused. So sit in it and mimik driving, i.e. apply the foot brake, indicate left and right. Does it start to smoke?

If you cannot get it to smoke without moving the vehicle then I would be thinking along the lines of stuck hand brake drum getting red hot and smoking.

If the engine is worn or a breather pipe is split then the engine bay will fill with smoke (Oil vapour) when you turn the fan on. it draws the smoke into the cab area.

Does it smell electrical? I had this. Scared the sh*t out of me as it was on the motorway. Pulled over and realised it smelt of hot antifreeze. Leaking heater pipe. Treated with radweld and problem solved. If you've got an electrical fault thats causing smoke, first its going to smell really acrid and second, something electrical is going to stop working.

diver said:

first its going to smell really acrid and second, something electrical is going to stop working.

Click to expand...

third, something might catch fire...

discomania said:

third, something might catch fire...

Click to expand...

I said that first.

Hi,

My Landy was up for an MOT last night and to have a look at the smoke issue as well. To say I was nervous driviing it up there was an understatement. Fire Extinguisher on the passenger seat just in case . Took so long coz my mechanic was away on holiday.

I was wrong, it wasn't electrical smoke at all. It wasn't the handbrake either.

It's had an oil leak since I've had it and my mechanic reckones the oil is collecting and being heated up by the exhaust, causing smoke to come into the cabin through breather holes in the transmission tunnel. To say I am relieved is an understatment.

Oh, and it passed the MOT as well, with just one advisory, "corrosion in the floor area" I think was the official line. I'm chuffed to bits.

Just need to refit the stereo (from when I had the centre console out to find the "eletrical problem" and it'll be back in daily use.

Thanks for the help.
Gareth