Hello,

I have somewhat of a sticky issue that I am hoping I can get some insight into.

Back in 2010 I bought a 2008 LS460L with executive package, a CPO with 27K miles on it. It worked just fabulously until I started hearing what sounded like water fall behind the front dash, it mostly happens when I accelerate from a full stop or from a slow down and subsequent right turn (yes kind of weird). The first time I took it to the dealer was in March 2012, the local dealer heard the sound, kept the car for 7days and 100 miles later they said they changed the water pump. I started noticing many issues right after this repair as follows:

(a) Coming out of a right turn (notice I keep mentioning right turns, it is sort of whacky as it does not do the same on left turns) it feels like that the engine will accelerate but the car does not seem to be move in unison but will lag behind it. Many times I can hear the engine revving but not so much as moving equally fast.

(b) I feel jerkiness in the car’s movements coming out of a full stop, accelerating on a uphill road, and just in general – not smooth at all.

(c) A few times the car actually shuddered while going uphill at about 35 – 45 miles per hour speed, and twice I have smelt something burning under the hood.

(d) I can still hear the water fall intermittently, it is starting to be more frequent and again it will happen most often after a cold start in the morning, then intermittently. Many times you can actually hear a soft water trickle behind the dash while the car is stopped say at a stop light. The real water fall as in a gush of water can be heard occasionally when accelerating from a stop or slow down. The tough part is that two times I have taken it in to the dealer, the car refuses to do it – murphy’s law and real spooky. Now the dealer is starting to think that I am delusional and they refuse to do anything about it.

(e) The performance on the car isn’t what it used to be at slow city stop and drive speeds – the issue is not noticeable at high speeds. I know it is behaving a lot differently after the water pump repair in terms that it is choppy and jerky in transmission. The dealer says there aren’t any error codes showing up in their diagnostics.

It seems like the water fall problem was never resolved by the water pump replacement, the performance on the car is come to an unacceptable point for me personally, the dealer thinks otherwise. Any insight on this is appreciated.
Thanks in advance.

 

Have you brought these issues up to the dealer since you were there originally, and if so, what have they said? Customer service at Lexus is typically exceptional.

I had a recurring problem with the tire pressure monitor system on my ES350. After 4 times at the dealer and many changed components, they finally correctly diagnosed the issue and corrected it. They always provided a loaner vehicle while my car was in for service.

You probably need to ask for a manager, and if the can't get the issues corrected, escalate, it to a regional manager. Is your vehicle still under warranty?

 

Their customer service is on the hook to call me back in 48 hrs, I sure hope they are able to figure out what's up with my vehicle. And BTW, I am having tire pressure issues as well, my pump shows a certain pressure but the vehicle sensor shows something altogether different - one more issue, I thought lexus vehicles were practically flawless.

 

the tire pressure is a setup problem. i believe dealership was supposed to inflate the tires correct and "reset" the sensors so it's in line with the actual value

 

Let us know any developments on the water fall/gush noise, my 07 ls460 is at the dealer for the same cause. Can't duplicate the noise, has to leave it over night to test cold. They tested cooling system pressure, no leaks. Was told by the master tech that there are AC drainage pipes behind the dash, anyone had problems with them???

 

my car does the same thing. Doesnt really bother me but I do wonder what it is. Its weird

 

If you look at the cooling system design you will see that the output hose (the large hose that connects the lower radiator reservoir to the water pump) is on the right end of the radiator. If the liquid flow through the radiator is insufficient then there will be an air bubble in the lower reservoir and the centrifugal forces of a right turn would cause the water to pool to the left, away from the output connection, and the water pump would be starved and the interrupted flow would account for the sounds in the area of the heater core. Causes would range from low coolant level, bad radiator core (due to deposits),collapsed upper radiator hose, bad pressure cap, cooling fan problem, cooling system pressurization problem.

 

Why would you believe that your pump is more accurate than the TPMS sensors?

 

Interesting. .my wifes 2008 Camry makes that same water dripping noise and no rain or car wash or R Kelly around anywhere

 

 

LMAO. Hilarious !!! I have the same issue and will mention it to the SA next time I go for service. I checked this morning and I can hear a little something when I launch from a stop but the radio is on so I never hear it unless I am listening for it

 

Back from the dealer, noise is gone after they pressure tested they system. Was told that this might have removed air bubbles from the system. Will see if it comes back.

 

Good insight, thought I was the only one. What I believe is that the water gush/dripping is also associated with or causing degradation in response to acceleration. I feel coming out of a 20 mile/hr right side turn I feel the engine isn't responding to acceleration and actually has a knocking sound - does it have something to do with worn out engine mounts, guessing. I am taking it to the dealer per Lexus cust service setup, so will post my experience.

 

While in th dealer checking on the gushing noise and test cooling system, dealer also upgraded transmission SW to relief the acceleration hesitation issue. I am not sure it has anything to do with the gushing noise going away but day and night difference in acceleration of my 07 after the upgrade

 

lmfao hahahaa