thomas1

Check the power steering pump for the noise. That noise is not normal.....The other thing you could do temporarily is remove power steering pump belt and see if sound goes away.

robbyk

Hard to tell but sounds like lifters to me, hydraulic lifters in this case.

Hydraulic valve lifters cushion the impact present whenever a camshaft eccentric moves the pushrod to open or close a valve. They work by using oil pressure present in engines to transfer motion in a smoother way than solid lifters would. In some engines, such as Overhead Cam (SOHC) or Dual Overhead Cam (DOHC) engines, the lifters transfer the camshaft motion directly to the valves.

Lifters can become clogged by dirty oil or foreign particles. If oil isn't flowing properly, they tend to make a chattering sound as the engine runs.

wdtony

Thanks for the replies.

@thomas1: I will check the power steering pump when I get some time, I didn't even think about that.

@robbyk: I hope it is a lifter. From what I've read I have the DOHC engine. It appears to have the cam lobe, then a lifter shim, then the hydraulic lifter and then the valve. I see no push-rods or rocker arms in this engine. Looks like in this engine sometimes the shims become worn or the lifters go bad like you said.

I have seen videos that have a similar sound, some were fixed by doing an upper engine clean yet in others, a new small block was required. And in some the lifter had to be replaced.

Sometimes it sounds so "thumpy" to me I fear it is a worn rod bearing. And other times it gets so quiet, I have no idea.

If it is a lifter on the DOHC, where on the engine should I listen with the stethoscope? Also where to place it to check for a worn rod bearing?

Sorry, I am an industrial machinery guy.... I am poor at troubleshooting cars.

thomas1

If it is the lifters could I suggest trying a oil change with Castrol Oil 0-30 European formula full synthetic oil. This oil in my old RX300 not only cleaned the inside of engine, but made the whole engine quiet. I presently do not use this on my RX400h, (same engine as yours) because of the 0-20 weight requirement. But at 120k miles on my old RX300 it was a significant change in smoothness of the engine...This oil can only do good. Please note also if you are not using full synthetic which has bettern cold start properties than you should. The extra cost will be offset with longer oil changes etc.

robbyk

I do not think it is a worn rod bearing, the sound is completely different, I am pretty sure about that.

First you would need to determine if the noise is coming from the 3 cylinders located in the front of the engine, close to the radiator, or if the noise is coming from the 3 cylinders located close to the firewall.

In your case this tool would be a good investment for you, as it is more precise.

rxpx40

iTrader: (1)

Wow,
good videos. Your second vid shows the car at cold startup. Engine rpm's seem a bit high to me comparing against my wife's 04 RX. (Which btw has no piston slap noise at startup) With the change in noise at varying temperatures I would suggest using your steth to check the front catalytic converter. Parts may have broken loose inside that causing a tap with certain exhaust puffs hitting. As the metal expands, it may become loose/tight as it cycles through temperature ranges. Just a thought. I've no experience with this happening on an RX.
Let us know what you find.

OceanView

I'm hearing 2 different noises.

On the second video I hear the clicking which sounds like lifter noise and a deeper toned tap tap tap that might be a rod knock/lower bearing sound (hopefully that's not it).

I have a similar clicking noise on my ES300 and I have been reading about an additive called Marvel Mystery Oil that may help. I have never used additives as they seemed like snake oil but this one seems like it has good reviews. At about $5 it's worth trying out and seeing if it works.
I am going to use it this weekend and see if it helps my car in any way.

If you do use MMO, please update us. I hope it works for you.

wdtony

I appreciate all the input.

I intend to ultimately find out what this sound is so when I do I will definitely post the findings. Or if I can rule anything out.

@thomas1: All oil changes have been done on time for the life of the car and according to records synthetic blend 5W-30 has always been used. I just changed the oil myself and used the same.I will consider using different oils but does anyone think full synthetic is much better than synth blend?

@rxpx40: Good idea to check catalytic converter, I think I have but I will check again just in case. I intend to do a complete check with a stethoscope or new tool to determine the origin. I have just been eluded so far after many days of listening and no success.

@robbyk: I have tried to listen to no avail, so this other tool can find the origin? I have no idea how much a shop would charge to isolate/locate the origin of the sound only. The dealership always seems so expensive.

@Oceanview: That tap, tap, tap is the only sound I am concerned with. I did put rislone engine treatment in 2 weeks before this last oil change and there was no change in the sound. it did clean a lot of dirt out of the engine (as the oil was clear before rislone but then dark when drained)

Thanks a lot guys, this forum is awesome!

robbyk

The headphone will help you isolate outside noise
It will help diagnose source of a bearing noise in a noisy environment. The headphone keeps out background noise. Metal pointer helpful.

See with the headphones you are not going to hear outside noise except for the one that is going to be in contact with the metal pointer. In any case it will be cheaper than Lexus or Toyota dealer.

Check out this tool also:
and this one:

thomas1

Yes full synthetic is better. I like the idea of bad cat, but would expect codes with performance issues. The synthetic I proposed is a true class 4 synthetic.

wdtony

Thanks, I'll probably have to wait to check a few things until after this blizzard. I'm in Cincinnati and I don't have a garage. At least I have some direction now. Will post just as soon as I have more info. If I do ever isolate the issue(s), I will make a video of the resolution.

wdtony

I thought the noise sounded similar to mine in this video. I know this isn't very scientific but I found this a while back and the problem was reportedly fixed with a top end clean. The bill shows Phyzix Fuel Kit ($58.00) and labor ($116.95).

This is the same engine as mine as well.

jbl-1985

I can hear the same noise in my RX330 but it is nowhere as pronounced as yours. It's very quiet and sometimes hard to hear even when warm. Now I don't have as many miles on mine as you do, but I've decided to ignore the noise as I have babied this car from mile 0, and I've accepted the fact that the car is going to make some noises. It can drive you nuts listening to this stuff and trying to figure out what to do to resolve it.

My ES300 has a loud tapping sound and originally I thought it was a valve, but upon inspection of the valve covers with a stethoscope, there is actually minimal valve noise. Mechanic told me it's one of the fuel injectors, and in fact I verified this with the scope....told me not to worry since if you hear the injectors tapping like that, it only means they're working...

wdtony

That makes me feel better. The sound I have is sometimes very hard to hear as well. It's only the times when it gets louder and more pronounced that really bugs me.

Update:

I did check yesterday with stethoscope and it seems like the noise is coming from near the pulley/belt side of the engine. It is most prominent between the heads as I checked the bolt-heads on the middle/top of the block nearest the timing belt side of engine. I checked the power steering pump but did not find the tapping sound there. I also checked the cat converter/exhaust pipe and there was no sound there as well. Also no sound from the intake plenum or throttle body. Fuel injectors make a distinct sound and both rails and all injectors sound similar..... but the sound I am concerned with is not emanating from the injectors.

RuninRoach

ok...so i didn't have any noise before i gave my car to the dealer to get the head gasket replaced. As a part of it they replaced the valve gaskets and spark plug gaskets. Doing all this required the items to be removed and put back....ever since, i have been having the exact same noise at the exact same times that you mention....

when i went back to dealer....'thats how its supposed to sound' or 'its not really covered since your car is out of warranty'.

i just deal with it these days.....will be issue when i sell this thing off but *sigh*