Light smoke and plastic smell from engine

[Reggie1986]

Hi there, need a bit of help diagnosing why we might have had smoke and a burnt plastic / rubber smell from engine compartment.

Noticed the smell after driving 3 miles at resi speeds, stopped the van a few hundred yards later, and a noticed bit of smoke coming out the driver-side vent ('normal' grey smoke, I think). Temp gauge at the time normal and no warning light on. Oil and coolant both at good levels. 

RAC guy reckoned it could be wires that are resting across the engine (you can see faint marks where the wires were sitting on the image), but I'm skeptical, as feel they would have need to melt significantly to produce that level of smell and a bit of smoke. 

https://imgur.com/a/t35nKaA

Weirdly, we couldn't recreate the problem running the engine for a long time, or on the 3 mile drive back home.
 
Any other thoughts and opinions would be so welcome. Thank you.

For a bit of extra info, we had a complete engine replacement last year when coolant had leaked out and the engine overheated (undertaken by a legit company). The smell was very similar to this occasion, although a lot worse, so I'm nervous about driving the thing again, should the same happen. 

TIA

Jack


 

[silverbullet]

Those are your spark plug leads and the inlet manifold does not get hot enough to burn anything other than your hands as it is water heated.
Open the air filter box and make sure that the element is clean, if it isn't then start looking at the crankcase ventilation system.
A fresh engine will have a little bit of piston ring blow-by until they have bedded in but it shouldn't be pumping a lot of oily vapour out via the tower and back into the inlet side.

[icosahedron]

Inspect the exhaust system for any wires or hoses that can touch it. It is the only part of the engine on the outside that can get hot enough to produce smoke.
  

[Reggie1986]

Inspect the exhaust system for any wires or hoses that can touch it. It is the only part of the engine on the outside that can get hot enough to produce smoke.
  

Thank you. Will get under the van and have a look in the morning 
 

[Reggie1986]

Those are your spark plug leads and the inlet manifold does not get hot enough to burn anything other than your hands as it is water heated.
Open the air filter box and make sure that the element is clean, if it isn't then start looking at the crankcase ventilation system.
A fresh engine will have a little bit of piston ring blow-by until they have bedded in but it shouldn't be pumping a lot of oily vapour out via the tower and back into the inlet side.

Thanks silverbullet. Will look into it. Good to know I can rule those out. My suspicion was the RAC guy was making sh*t up. If it had been the wiring you'd see it. Thx...

[Robsey]

Sadly, if it does have a diagnostic port some patrols are clueless.

I have had more mis-disgnosed breakdowns than I care to think of.
Thankfully, a bit of logical thinking allowed me to fix the cars myself.

If it smoked at first, but has not returned since, I would be tempted to think it may be something from the rebuild that has simply burnt off.

I am not saying that you are paranoid, but I am saying try to enjoy driving the van rather than stressing about it.

[Mocki]

Coolant ? Is the cap leaking, or the res cracked ?
Looks like it’s right above zorst ?

[Reggie1986]

Coolant ? Is the cap leaking, or the res cracked ?
Looks like it’s right above zorst ?

Very good spot Mocki. Me and the RAC fella checked the coolant, which was full to the brim, and a little spilled out...
 

[Reggie1986]

Sadly, if it does have a diagnostic port some patrols are clueless.

I have had more mis-disgnosed breakdowns than I care to think of.
Thankfully, a bit of logical thinking allowed me to fix the cars myself.

If it smoked at first, but has not returned since, I would be tempted to think it may be something from the rebuild that has simply burnt off.

I am not saying that you are paranoid, but I am saying try to enjoy driving the van rather than stressing about it.

Thanks Robsey. Yep, I did wonder if whatever was burning had burnt away. Fingers crossed it's a one-off. Thanks for the sage advice, and I'll try my best to not stress.