Today after a long drive towards the end I was getting whiff of smell in the cabin through the vents that smelt a bit like hot plastic or even possibly burning/melting plastic or rubber. After I parked up I inspected the engine bay and couldn't smell it there. But from outside the car specially by wheel area I was getting a whiff of the smell. Just couldn't figure out where it's from. I did notice on that side front wheel the dust cover rubber for the shock absorber is split and has dropped down and us resting at the base. But that shock absorber rubber dust cover shouldn't really be rubbing against anything or generating friction to burn it should it? Strange thing is I couldn't smell from the engine bay but could get whiffs from left front wheel area

 

@lexus-is2 Check your headlights. Remove the bulb covers, disconnect the wiring harness and remove the bulb. Take a look at the wiring harness and bulb. Is the wiring harness connector melted or the bulb base melted? I have seen problems with people using cheaper aftermarket replacement bulbs. The harness connectors and bulb bases short-circuit and melt the housings. It's a fire hazard and insurance claim waiting to happen.

 

It could be a sign of the alternator going bad, at least it’s happened to my IS, i did smell the plastic burn through the vent and after the car is stopped and about a month later my alternator died

 

Headlights and everything seems fine. All original bulbs in there. Next day after this smell I went for a drive and initially as car was warming up the smell came for a little while then disappeared and then it completely disappeared after that. I then drove again and still no smell.

Ouch now that is worrying. Anyone else had plastic/rubber kind of smell related to alternator? what exactly is the plastic/rubber burning if it is the alternator?

 

Well if your car continues to have that plastic burn smell? Turn off the car and smell under the hood where the alternator at to smell if the burn smell come from there? If it is that is the sign for a bad alternator, i was lucky my alternator died when i just pull off the highway and get off the ram and i was able to drive into the cvs parking lot and died in the middle of the parking lot

 

There have been a few AC compressor failures. Set the AC to lowest setting and observe the AC compressor and belt. Confirm the smell is not from a slipping belt.

 

Any updates? Like was mentioned before, this happened as my ALT went going out on me and then finally TOTALLY gave out with a nice plume of smoke. LOL!

 

Sorry for late reply. Have had a nightmare with this. I installed the new aftermarket alternator, changed the idler pulley as old was noisy and installed a new OEM belt. Connected up the negative and when I started the car it made a really loud whining sound almost like a very bad version of belt screeching. Went to check it and the alternator was smoking a lot of smoke. So turned it off. So now need to return this aftermarket alternator. I'm wondering could it be the belt or the new idler pulley? What are the chances of new alternators doing this? But the smoke definitely looked like it was coming from inside the alternator itself

 

Where exactly is the smoke coming from, how was the alternator positive wire when you changed the alternator? You need to check to make sure the battery is getting at least 13.XX volts to it when the car is on idle.

 

The smoke looked 100% like it was coming from inside the alternator and out through the vents/fins of the alternator. The noise was extremely loud. The alternator positive cable was just loose when I removed the old alternator but I had disconnected the negative battery terminal so it didn't short or anything and i've inspected the fusible link and it's all fine. I have another thread regarding the same issue with a recording of the sound here: https://www.clublexus.com/forums/is-...-rotation.html

Maybe a mod can merge these two please?