462HO

I bought this car a few weeks back, a Starfire White, Comfort package, ML and 54,300 miles. I just picked up a Platinum extended warranty for 5 1/2 years 48,000 miles, which fits my driving habits well.
I am very excited about the car and have already learned a lot by browsing this great forum.

So, all is well, BUT I noticed after the purchase from a private owner that the car has the dreaded knock. The car runs and idles perfectly. Of course, the fuel pumps and/or injectors make noise, a bit diesel like, but this is a distinct tap or knock heard very well at idle with windows rolled up, it doesn't matter. I first noticed it sitting at a traffic light next to a pick up truck, thinking that guy has a bad lifter. Then at another light, another pickup with a bad lifter!?!

So, I immediately took it to my local Lexus dealer, as my powertrain warranty expires Dec. 27, 2017. The service guy heard the tap or knock said they will check it out. They ended up replacing one of the fuel pumps saying they isolated it with their stethoscope and it was noisy. He said the noise was gone and he sent me on my way. As soon as I pulled out and sat at a light, it was back. It is intermittent most of the time, it is there, though.

The service guy said bring it back in, and let the shop foreman listen to it, and maybe listen to a few other similar vintage LS's, if they make the noise, it's a characteristic, if not, it's a problem.
The foreman heard it and acknowledged it and it was intermittent, said it's the pumps, injection and that it has been ongoing with Lexus and they just started replacing fuel pumps to remedy the situation. I mentioned piston slap, and he was dismissive, saying Lexus doesn't replace engines due to that. He said it is not the other pump either. On the service ticket, they stated no abnormal noise was heard, despite him hearing it

I called back and arranged for them to get other LS's from used cars, and listened to them. One was quiet, the other had the diesel sound, but not the distinctive tap or knock like mine. The service guy had the foreman listen, and he commented to the service guy that there could be some piston slap and the pump/injector noise. The service guy suggested that we have the regional Lexus rep listen to it when he is in town in January. My guy offered to write up a ticket for my visit that day, and I asked him to document what the foreman said, and my findings listening to the others. I don't have a copy yet, as he has been out sick a few days and says he will get it to me.

Sorry for the short novel, but I am very concerned about getting this issue well documented before my powertrain warranty expires.

Does it sound like I am handling this properly, or is there anything else that I should be doing?

Thanks.

UDel

Sorry to hear about that. Needing a new fuel pump, knocking, piston slap, in a 2012 LS with less then 60K miles does not sound normal, it is pretty concerning and disappointing especially if they are going to charge owners to fix this issue. I remember reading some 07 and and 08's had some valve/engine issues but they were addressed in later models. I think you are going about it right, be diligent and document everything, they should not dicker over a cut off date when you have made the efforts before, they really should address the issue and not charge the owner in any case.

Nospinzone

I think you are going about it the correctly, particularly in demanding written acknowledgement of the issue with the warranty ready to expire.

As an aside, obviously I'm not there to hear it, but I seriously doubt it is piston slap. I've encountered piston slap in another vehicle. It does not make any noise, what happens is the engine vibrates like hell at higher rpm's.

roadfrog

Sounds like they're in your corner. Just need to be patient now. Enjoy your Christmas and try to relax. Your car is fine.

joedaddy1

iTrader: (1)

the normal direct injection perhaps?

roadfrog

I think so, but he seems more concerned that it's something worse. All our cars do this (as do all DI engines). That's why I said it'd be fine.

sktn77a

iTrader: (2)

I've heard this on an LS460 when I was looking for my2014. If it's the same noise I heard, it's definitely not the injectors (the injector "ticking" could be heard behind the other noise). It does sound like a diesel Mercedes has pulled up next to you. Definitely not "normal" or aceptable.

sha4000

iTrader: (1)

Can we get a sound clip of the engine? The 460 is louder than either my 400 or the 430 that i briefly had. I too attribute it to the DI but it is very loud on my car even after a 60 minute highway drive.

462HO

Yes, I will try. Last time I did on my iphone, it didn't pick up the noise well at all. I don't know if there is a way to make the microphone more sensitive. Will try again. This noise exists when the car is fully warmed up, not like piston slap I am used to in cars that is mostly present when you first start the car.

Doublebase

Sounds like normal direct injection noise to me, which is loud if you're not used to it. Definitely not piston slap, all the piston slap I've ever heard goes away when the engine warms up. Direct injection is just loud, Companies have gotten better in limiting the noise but it's still there...it used to be even worse.

sktn77a

iTrader: (2)

Note that the injector "ticking" is audible from outside the car with the hood up but shouldn't be audible inside the car. If you can hear it inside the car then it's probably the pump. You should try to get them to confirm this and maybe replace it.

joedaddy1

iTrader: (1)

sktn77a

iTrader: (2)

Then it's probably the pump.

UDel

Is replacing a pump DIY? How much is it to do at a dealership?

sktn77a

iTrader: (2)

If you're a reasonable DIY-er it should be doable: