mcmcomput

In 2010 i purchased a 2005 Lexus GX470 w/ 52k miles. It had 2 previous owners and you could tell it had been garage keep and most likely not their weekday car because low miles and 3rd row was in mint condition. Up until late last year the car has been great. I use it to tow my boat and the only thing besides regular oil/filters and its 60k checkup was to replace the drive shaft for the TSB/clunk noise on stopping.

I am currently having two issues that have been becoming worse.

1st is the knocking or tapping noise in the engine compartment. Below is a link to the video. This was after driving for approx 15 minutes. It doesn't do it 10/10 times, but is probably happening 1/2 the time now when i drive it. Oil is 10W30 Full Synthetic by MobileOne and just replaced today to see if that changed anything. I purchased 2 replacement knock sensors a few weeks back but haven't had the time to break it down to swap them out. Figured since the belt needs to be done at 90k and my car is 10yrs old I might as well replace the timing belts at the same time. When the AC is on or car is in drive it doesn't knock strangely enough. In the video you can hear the AC click on/off and knock when its off. I'm hoping this isn't a bad engine or rod or something... Thoughts?


2nd is the steering vibration. I noticed there is a TSB on that for replacing the steering column and other parts and assume I should do thing soon as well. Depending on the payment or temperature it will do this at times around 60ish MPH. Again, its not consistent, but is very noticeably while driving when it is. Tires have approx 40% tread remaining and only the driver side tire seems slightly more worn on the inside than the outside. Thoughts?

mann777

That knocking seems a bit loud. Have a look on the belt and the water pump bearing kit. And also have the Throttle body cleansed. Here is the O2 Sensor chart replaced for GX ( check the attachment for reference ) . Regards steering issues, possibility are that the tire would have flat spots due to long periods of storage. Have a look and decide which one requires replacement. Don't target the steering repair immediately ( that should be the last resort ) After replacement of tires do a Zero Point Calibration. And let us know.
cheers

chiph9

Something cheap and easy to check is seeing if there are any loose spark plugs.

17.5 N-m for the plugs = 15ftlb.
7.5 N-m for the coil-pack bolts = 66inlb.

Chip H.

IanB2

That knocking is louder than I'd like to hear, I 2nd double checking the spark plugs for tightness.