2012 RX350 with 102k miles.

After a long road trip the next start I noticed a fairly loud engine whine. Seemed to be RPM dependent. A short drive later stop/start again it went away. Now a few months later it returned. I looked under the hood and noticed a faint burning smell (not electrical to me) and a tiny bit of smoke on the left side of the engine. Sounded like a power steering whine but research indicates it uses an electrical system.

I've got an appointment with an excellent indy shop but he's booked for a week so I'm trying to determine if my car is safe to drive and possibly pin down a diagnosis.

• Engine has oil
• Smoke occurred after only a short (3 mile) drive and sitting all night so something got hot quickly and burned
• 3" diameter spot on garage, could be motor oil
• Car has towing package

Other research indicates a well known oil cooler line but some sources say my 2012 won't have the rubber one (of course any part can fail), other source indicate it could have it.

Anything else I can check? At this point I'm thinking I should err on safe side, not drive until my appointment.

Thanks

 

I would not drive it before inspecting your oil cooler line to see if it is rubber and leaking or metal. If you can lay on your back and look up under the front bumper you can see it.
You may be able to see part from above. I forget if there is a trim piece to remove to see the bottom part of the engine.

Here are links to photos (or look at youtube where there are several videos. Then look around for other leaks. If the rubber hose is there and leaking do not drive it as it could burst and spew all your oil out in before you can see the oil warning light and shut down the car.

Otherwise I suspect an idler pulley on the serpentine belt may be bad.

​​​​​​Here is the rubber line



Here is the metal line
​​​​​​

 

Thank you for this excellent info. I looked with a light earlier from above engine but couldn't make out the pipe and saw only what I believe were AC lines. I'll go underneath and see if I can find this part.

I agree that driving it if it's an oil leak here would be super risky.

Thanks again.

 

Here are the metal lines

 

I tried looking underneath but can't see it. There is a sloped plastic air dam at the front of the car below the engine held on with both bolts and those dreaded plastic push tabs. I'm thinking it must come off first but I'm going to try to get underneath the nose of the car first.

 

Oil cooler pipe is definitely a metal one unless there is another pipe that looks just like that at the front, passenger side. It is visible with air dam in place if you can get under the nose of the car.

Spot on garage floor must have been AC condensation. It is gone. I guess I was paranoid so it looked like oil. No spots visible now. Looked all underneath and one spot has old looking and very light oil stain. Nothing wet, nothing dripping, nothing black/brown oily.

Given the location of the belt and pullies, the fact that it whines pretty loudly and gets louder with engine speed, a part that moves with the engine makes sense. I'm not a mechanic at all but idler pully is feasible to me. I'm still not going to drive it unless emergency or to the shop next week when it's time to take it in.

Thanks again.

 

It could also be the water pump if there is more of a rattling noise also in that area. Water pumps are a known wear/failure item as the mileage racks up.

 

A mechanic's stethoscope would be very helpful in this situation.

 

At this point, given I work from home and my wife has a car it's just sitting until next week when my appointment is. The shop I use is great but they always have a bit of a wait to get in. Whatever is wrong the car is young enough and valuable enough to me not to replace parts on it myself.

Plan is to start it the day before and see if it whines badly or smokes. If it doesn't I'll drive it in, if it does I'll get it towed over.

 

Check voltage at battery with engine running…if it’s less then 13 volts your alternator is what was smoking.

 

Update: Got a call from my mechanic. He said it was a pulley, hard to get to, didn't have time to do it today. He listened to it with a scope and said it's safe to drive, just don't "drive it to California". Saw nothing leaking. Got me on the schedule for next month.

Background here is that this is an older gentleman. As far as his honesty goes, I trust him 100%. It's 2 guys, they are trustworthy and over the years have done some quick things for my wife and I at no charge.

However, when I drive this car 5 miles you can smell something burning after you park it and get out of the car. I'm tempted to take it somewhere else to have the work done, probably at 2x the rate, so I don't have to worry about it. When I asked him could the bad pulley be causing the belt to burn he said there was a spring adjuster (something like that, he has a strong accent and English is not his first language) in it that would prevent it from happening. Finally I'll say this started on a long road trip a couple weeks after he replaced the main belt for me. Could be coincidence but thought it I'd mention that too.

 

It appears you have a bad idler pulley. They do fail as the mileage grows. There is an automatic tensioner which also could have failed. It is strange to happen soon after he installed a new serpentine belt.
Is your mechanic aware of the smoking smell issue after 5 miles? That may make him want to repair it sooner.

You may want to get a couple of other estimates and evaluations of your issue. The belt could also be damaged by this, or maybe he installed the wrong belt.

 

I did mention the smell. I think you need to drive it a bit to reproduce as he didn't see it. I'm still not driving it except for rare occasions for 2 or 3 miles max.

I'm going to call another shop today to try to get it looked at. It seems to me something is rubbing the belt under load causing it to smoke and produce a burning smell. It does whine at idle but I think the problem isn't as bad as when you drive it a bit.

 

Maybe he damaged your automatic belt tensioner or something else installing the belt. It is extremely tight to work in that area.

 

Took it to another mechanic. I haven't been driving it at all. Loud whine at start, loud whine on the way there, about half way there it had quieted down. So by the time I pull in it's pretty quiet.

Mechanic says it looks fine. Belt was in proper position. Maybe it was installed incorrectly but it was fine now ???

They want to replace the radiator, says there is a leak at the top, send a picture of white scale along the edge, hard to orient exactly where that is. Says that is the smoke and burning smell. I'm pretty damn sure the smoke I saw was coming up from the side of the engine. I declined radiator replacement.

I'm back to square one , minus some diagnostic fees, going back to original mechanic next month.