After starting up my IS250SE auto from cold, there is a slight tapping noise from (I think) the engine when accelerating. This is reminiscent of tappet noise and gets faster with engine speed. It is not apparent at idle, and only appears if the engine is under light load (accelerating on the road). The car has done less than 17000 miles and the noise wasn't there until recently. The noise disappears after a few minutes - presumably as the engine gets hotter. The USA LOC web site mentions what seems to be something very similar although for an IS350, and the "answer" is that it is "harmless" piston slap. I am old enough to remember old-fashioned piston slap and my noise seems to be rather more like tappet click. I don't recall piston slap ever being "harmless" either - it was typically an indicator of severe wear. Has anyone else had this problem or know what is is?

Is it like a constant noise that comes when accelerating. does it happen when reving on idle? i've got a similar issue and have had it for a year now and have learnt to live with it, it only seems to come if the car has been left in the cold for about a day and doesnt seem to be that bad on hot weathers. like in the summer I couldnt even notice it. But now that cold weather is back I've started hearing it again. I haven't heard anyone else have the same problem. I know there is service bulletin for a brief tapping noise on startup. I've had this service bulletin carried out on my lexus but this other noise still remains.

The noise is not just one or two knocks - it is constant in synch with engine speed.

Further to my posting above, the noise is not there when revving the engine while in Park, and is only apparent when the engine is under load (ie. accelerating ) and cold. It lasts for 2 or 3 minutes and then quickly reduces in volume until it is inaudible. I am fairly sure that it is not the knock on startup that is referred to in the service bulletin. The noise is even/steady (ie. it is not as though the tap occurs in synch with only one cylinder) and is somewhere between a tap and a knock in sound.

definately sounds exactly like the noise i get. i used to also get the startup crank noise and had the bulletin carried out, hoping that the both might be linked in a way. But, it definately aint linked as that noise still remains

My car began making the same engine noise (tapping noise when accelerating after a cold start) about one month ago.

It has ~48K miles.

I just brought it to the dealer. They agree that there is an unusual noise, but are not sure what to do.

They have scheduled an appointment with me and the factory service rep. in two weeks.

My fear is that he will say the the noise is acceptabe or normal. Believe me it is not.

If anyone has had a similar noise that was successfully repaired please let me know.

makes the noise in park,,,,?
i'd give the gearbox an oil change,
any manuals have this?

johny

Sorry folks, only just read this post. There is a known fault which shows itself on cold start up which could be your problem, open this link to see the original post. Bratman 91..I know you have stated that you have had the TSIB work carried out on your car, but do you know exactly what was done? http://www.lexusownersclub.co.uk/forum/ind...309&hl=TSIB