Hi everyone!

I'm new to the Lexus family, but I'm really happy that I did the switch from Nissan to Lexus.
I have recently bought a 2008 IS250 RWD with 106k from someone else and I recently noticing a fairly often occurrence of the startup rattle that lasts only for a second or a split of a second. The car was due for an oil change then so I took it for an oil change and 105k service to a Lexus dealership. I mentioned about this startup rattle sound, the service advisor said they didn't hear anything strange when they did the inspection, and he told me it was a fairly common issue with the IS series. He told me there are cases when this was "fixed" but the rattle still comes back later. He also said that it would not hurt much since my car is still running fine.( it's really smooth, especially when I was test driving it hence I made the purchase, and it's still running smoothly, but there is that ****ty rattle sound)

The engine oil used at the dealer was claimed to be Mobil 1 full synthetic, and the rattle sound comes on when I park the car and not use it for a shorter period of time (no longer than 3 hours or so). But this rattle doesn't occur during morning cold starts or after sitting the car for a long period of time... I am just very annoyed with this sound, and I know there's been a lot of discussion about this already, but I just want to know for those who tried switching to Castrol Edge, does it really get rid of the rattle sound??? I'm very intriged to try it for my next change.

Thanks guys!

Best,
Eric

 

You're not alone. This issue bothered the heII out of me when I first got my car. Like you said, it'd only happen when you fire it up after a short break but not first thing in the morning. But since my car accelerates fine and idles like its not on, I don't think it's too big of a problem.

ps. I use Mobile-1 Synthetic

 

This is a problem on some IS350 and 250 -- though generally it happens on cold starts (you can search about cam gear rattle). For the 350, there was a recall because it could cause some engine damage. For the 250, it was a TSB because the car should work fine though the rattle is annoying.

 

same problem and i always think its the cat.. lol since i have that rotten egg smell

 

So, have you ever tried the Castrol Edge full synthetic? I'm just really curious about its effect, but my oil was recently changed so I won't be changing oil anytime soon.

 

Have you tried anything to get rid of it? Or you just get used to it and live with it...
It seems like it's not causing any substantial problem to the engine yet. But that sound just doesn't encourage me to think positively...

 

Have you continued to have the rattle issue AFTER the recent oil change?

 

Yes I do. I got the car 3 weeks ago which is due for an oil change. And so I brought the car to the dealer to do an oil change with the 105k service. The rattle is still there, and I've been trying to add a bit more oil to see if it helps, but so far no luck. The engine still makes that sound when it sit for a while, but it doesn't make that sound when after sitting for a night or longer... Super strange...

 

Without hearing it I can't be sure but what you describe sounds like the following problem.

Toyota has identified certain Lexus models built between 2006-2011 with this VVT noise problem, and issued a voluntary recall.

Bolts used to secure the variable valve timing control device can become loose, causing the vehicle to stop while being driven. Early warning for this condition can be identified as a brief rattle noise for approximately 1 second upon a cold start-up.

Description of Problem:
The subject vehicles are equipped with a Variable-Valve Timing (VVT) system which controls the camshafts to provide optimal valve timing under certain driving conditions. The bolts used to secure the housing and sprocket of the intake-side VVT gear assembly could become loose due to abnormal impacts generated within the gear assembly immediately after a cold start-up.

If this occurs, the VVT gear will not control the intake valves correctly. In certain cases, the VVT gear housing and sprocket could separate and result in the engine stopping while the vehicle is being driven, increasing the risk of a crash.

Toyota theorized that the condition could be related to an engine noise issue at start-up being investigated on certain engines. The VVT internal component could rattle when the lock-pin, which latches to the VVT housing and secures the internal components to maintain the camshaft in the most delayed position, unlatches at cold-start. Toyota conducted reproduction testing and was able to duplicate noise but was unable to duplicate the loose bolts condition.

Through reproduction testing, Toyota confirmed that, with the lock-pin disengaged during a cold engine start, the impact force between the VVT internal component and the housing could become larger if engine oil, which is pumped into the VVT unit to control the position of the camshaft, drains back into the oil pan while parked. In addition, Toyota theorized that the impact force varies in specific engine types due to cam profile and intake valve spring load. Toyota continued its investigation and testing to clarify the relationship between the impact force exerted inside the VVT housing at cold-start and bolt loosening.


This is definitely something you want to fix. It will only get worse as time goes on and you don't want it to fail completely.

 

Thank you for the very detailed text about the potential risk. But my car does not rattle during cold starts, most of the time that rattle sound comes on for a second or less when I sat the car and not drive it for 30 minutes or a couple of hours. The engine is still warm, yet the car makes that rattle noise when I started it up...

As for the voluntary recall, isn't the recall only for IS350? Please give more information.

Thanks!!!

 

I was under the impression the IS250 can have this problem.

That rattle you are hearing is more than likely caused by locking pin failing to lock the cam gear until oil pressure is built up. It doesn't need to be cold. It just needs time for the oil to leak back down into the crankcase.

 

isnt it the Cam Gears?

 

got use to it i really think its my cat because its under my car and not the engine or cams like everyone saying

 

Should I be very worried about this? I'm seriously annoyed by the sound of it every time I hear it.

 

well, according to Lexus, on the IS250, it's not a big issue for the car to rattle on cold start other than an annoyance. Since your car doesn't do it on cold start, it's hard to tell if it's the same issue or a different issue.