Hi everyone - long time lurker, first time poster - could use some advice from you!

My wife's 2011 IS250 developed a knocking sound over the past few weeks. It's gotten progressively worse and today it's sounds loud enough to be very obvious. I am not a mechanic in any way imaginable, so please excuse the ignorance here: It appears that the noise is coming from this part, which also appears to have a wobble when the engine is on and it's spinning. This black cap thing appears to be tight when I push it with the engine turned off, but I'm quite certain that's the culprit that's causing the rattling sound.




I'm taking the car in for check first thing in the morning, but in the meantime, could someone educate about what it is that I'm looking at and offer any guesses as to what the problem might be?

We've owned this car since new and only have 45K miles on it, always services by dealer. No prior issues of any kind.

Thanks in advance!

 

I'm 99.99% certain the noise/issue is the water pump.....get that fixed ASAP

 

Ah, thanks - now that you've helped me identify the part, I did more googling and found a bunch of other reports of failing water pumps along with videos of what a failing water pump sounds like - it matches mine. Darn it... looks like the repair can be as much as $1K at a dealer, what a bummer.

Given the wobble - I'm guessing whatever bearings/bushings that are failing - would a repair like this require drive belt change too since it's attached to it?

 

Why would you take it to dealer for repair? Watch the video, order all the parts needed from RockAuto, take it to reliable independent mechanic and save yourself big chunk of money. Here's a video

 

Sometimes taking it to a dealer pays off... despite the car being 4 months out of warranty, I requested they open a claim with Lexus and the replacement was approved 3 hours later at no cost including a loaner. It's our 4th Lexus and the car only has 46k miles so maybe low mileage and customer loyalty played a role here. Either way, Lexus is covering it 100%.

That said, on my way to drop it off, the bearings really started to give out and the belt developed an obvious squeak in addition to the wobble noise, so looks like I got it in just in time. I watched that video and though it doesn't seem all that super complicated, if I had to pay to of pocket I'd still have the dealer do it... time and convenience alone is worth it. I called 3 other small shops and all came within $80 of what two local Lexus dealers quoted me yesterday, all claiming it to be a 5 hour job.

Either way, thanks for your responses!

 

That is an excellent outcome, glad to hear your car is taken care of