DeeLexy460

Hello Everyone! I'm new at this so forgive me if I mess up at some point! About 3 months ago I noticed at times my Heat would blow out cool air. This would happen mostly when I was sitting idle or in traffic in a "stop n go" situation. I did some research and found out that my Coolant was on the low end. I bought the Pink Coolant from the Lexus dealer and filled up.
I checked the levels again a few days later and it was low again. So I topped off again and looked for any puddles underneath the car when sitting, I paid attention to any smells, and looked to see if I was blowing white smoke out of my exhaust. NOTHING! My indicator stays on the middle range and never runs cold or hot. I topped off after seeing that it was low again and didn't have to put as much in there, but it definitely was low again. It's now been about 2 weeks and it's still at the same spot (near the low indicator) but it doesn't seem like it's getting any lower.
I have done more research and I cannot find any issues with the 2008 LS460's having issues with head gaskets or coolant issues.
I recently had my bumper replaced at the Lexus dealer Auto Shop because of a pothole I ran over that dinged it (also bent my rim)....I know this might not have anything to do with it but I thought I would add this tid bit since I didn't notice the issue until I got it back from them!
I'm just really at a loss...does anyone have any ideas before I bring my car into the EXPENSIVE Lexus Dealer where I KNOW they are gonna try to get me for MORE ISSUES....Thanks!

jmcraney

I think you have done all of the right things: the coolant is at the correct cold-level, the car's operational temperature is at mid range as indicated by the gauge, heater output is acceptable, no coolant odor, no coolant puddles or visible leaks, and everything is stable for a couple of weeks.

There are lots of possibilities to explain the need to add coolant. It is possible that some sort of maintenance such as water-pump replacement or hose replacement was done and the technician failed to get the coolant adequately replenished - that is easy to do when time is money. Another possibility would be that the coolant reservoir cap was not adequately tightened at some point and that could allow the boiling point of the coolant to be lowed because it was not pressured, allowing loss as steam.

Using the coolant premix is the good thing to do. That avoids the need for mixing and checking with a hydrometer. The premix might be less expensive at a Toyota dealer.

Be sure to tighten the cap on the reservoir until it clicks. The click indicates that it is sufficiently tight to allow the cooling system to pressurize.

Here are some clips from the owner's manual that might be helpful:

iampraneel

iTrader: (3)

Hi DeeLexy460,

Did you find a resolution to your problem? The same thing is happening to my car.

VIS250P

iTrader: (1)

Check the water pump????

iampraneel

iTrader: (3)

Checked the WP. No leaks and its not dropping below the low level mark in the reservoir.

jmcraney

I am trying to understand your concern. Is it that the quiescent coolant level is always at the low level mark no matter how many times you fill it? Mine works that way and has been trouble free for the past 5 years. I think that is just normal. Some of the liquid is dumped through the overflow when it expands due to increased temperatures until it gets to the "normal" level. Most car cooling systems work that way.

iampraneel

iTrader: (3)

I guess its fair to say there isn't really a concern as the car seem to be running fine. Just odd that it would drop at or below "low" when the car is cold. Its very misleading. I also noticed on my IS250, when cold, its below the "low" level. I guess its just "normal" for these cars.

zazzn

I'll tell you exactly what it is....

I have an IS-F and I got tired of topping up.. After having the water pump replaced and it's still leaking, I found there is a transfer pipe with two Orings which seems to be the cause of my leak. I'm fairly confident it's the same as yours.

No coolant on the ground, no heat unless you rev high or fill up the tank. Gurgling behind the dash every so often.

http://www.*******.com/parts/p_U_200...HA_1603.2.html part 16322.

ah it wont post it... go to toyodyi dot com and search out the isf or the ls460 under coolant on the second page you'll see the stupid little exchange.

To get this resolved, I had to take out half the wire harness, intake manifold, first set of injectors second set of direct injection injector and I'm still not able to take out that pipe. It looks like you have to disassemble the whole front of the engine. or try and remove the heat exchange unit. I'm not sure what to do at this point because It's virtually a front engine rebuild to get to that pipe.

Anyways, if your lucky it may just be a defective waterpump as many of the IS-F owners have had.

sktn77a

iTrader: (2)

Air in the cooling system from letting it run low? BMWs are notorious for this. Don't know about Lexus. Speak to the service department at your nearest dealership. Either way, it needs to be fixed.

roadfrog

I have the exact same issue with my '08. No obvious symptoms or problems, other than I keep adding to the full mark and within a few days it's down to the low level and stays there. Sounds like it must be normal, but I'm gonna keep an eye on it.

jwin

iTrader: (16)

Ls460 has a problem with the overflow port on the radiator cracking due to it's placement near the top cover. Anyone that leans on the cover without knowing the port being there will probably crack it. A small crack will cause fluid to leak but not enough for you to see a puddle at all hence why your coolant tank is running low. When you go buy a new radiator they redesign it so the overflow port won't crack anymore. Very common problem.

chpten8

Go to PepBoys and grab a radiator tester, with the system cool pump air into radiator and watch the needle drop, as it drops listen for hissing. It is much better to do this with the system cool, the water will stay water instead of vaporizing due to heat. The tester runs about $90, it's a loan tool so you'll get that back when your done using it.

randomwalk

mine is low too...I need to check it tonight. Where is this overflow port?

1BlinkGone

It has to be going somewhere. It's not "normal".

RR601

Just thought I would add to this discussion.
I consider the LS a well built car. But also it was a very poor design the way it is to add coolant.
Never had a car ( including older LS) that took one tool to add coolant. This model takes two tools. One to remove the trim plugs another to loosen the air intake pipe. All this to just get the top off.
All they had to do was move the cap an inch over and then at least it would only take one tool.
This should have been easy to see and change in the design