Heating In A Gs430

[Glenn]

Hello all,

Picked up my 2001 GS430 a few days ago now, today i noticed that the heating wasnt blowing very warm into the passenger side even though the dual temps are both set to max. I have also noticed like a gurgling sound behind the dash when i rev the engine? Anyone any ideas? have a horrible feeling it may have an air lock or something? hence the bubble sound when i rev the engine.

If it is air in the system i am wondering how its got there and how do i get rid of it. I am worried as the last car i had with a simular problem needed a new head gasket in the end and dont fancy doing that on a GS430

Any ideas would be very greatfully recieved

Glenn

[dave1]

Was it purchased private ?

[Mark W]

Take back if bought from dealer

If private, lift front of your car (on ramp or park on incline with front higher) open the rad cap and start car and leave running a little. If it's an air lock this should sort.

Ps. Obviously don't open rad cap if your car is hot- you'll get very very scalded

[Glenn]

Thanks for the advice, will have a look tomorrow in the day light. Just backed it into a damn lampost tonight whilst collecting the chinese take away!!! Not having much luck so far?

PS the bang might have released the air lock

[Mike_B]

I think it's likely to be coolant levels causing your heating issue. Check the amount of water in the rad (when cold, as Mark said!) Mine used to gurgle when you first started it up, half a litre of water in the coolant and the problem went away never to return...

[Glenn]

Thanks for the replies, I have added about half a litre of coolant and the heater seems to have been sorted, fingers crossed but every time I check the coolant level it is always below the bottom line. It doesnt matter how often i top it up or how many miles i have driven its always below the min line when i check it? I cant see any signs of a water leak and the engine temp is always just under the middle mark on the guage and never goes any higher. Not sure why this is unless the cap on the expansion tank is faulty or something? Think it will just have to be a characteristic of the car as it doesnt seem to be causing a problem, it just niggles me that the level never stays on the max line?

[Mike_B]

Well, it must be going somewhere... Water isn't compressible, so if you keep adding more then it's either leaking out somewhere or else there is a big old airlock somewhere that you are slowly filling up!

Can't remember off-hand whether you are supposed to check the coolant level with the engine warm or cold; I'd guess cold because you'd need to be careful of escaping steam if you opened it up whilst it was hot. How much more water have you added now, compared to when you got the car?

[stables555]

Well, it must be going somewhere... Water isn't compressible, so if you keep adding more then it's either leaking out somewhere or else there is a big old airlock somewhere that you are slowly filling up!

Can't remember off-hand whether you are supposed to check the coolant level with the engine warm or cold; I'd guess cold because you'd need to be careful of escaping steam if you opened it up whilst it was hot. How much more water have you added now, compared to when you got the car?

The last time this happened to me the head gasket had blown and the water was going straight into the cylinders and blown out the exhaust, a sort of steam hybrid! Hope in your case it's something entirely different.

[Glenn]

Well, it must be going somewhere... Water isn't compressible, so if you keep adding more then it's either leaking out somewhere or else there is a big old airlock somewhere that you are slowly filling up!

Can't remember off-hand whether you are supposed to check the coolant level with the engine warm or cold; I'd guess cold because you'd need to be careful of escaping steam if you opened it up whilst it was hot. How much more water have you added now, compared to when you got the car?

I agree Mike, water cant just shrink? I have noticed something odd, on top of my radiator next to the cap there is like an over flow pipe which is part of the rad, but no rubber hose attached to it or anything? i.e. it goes nowhere? I am sure that on other gs430's i have seen a pipe going from here to the cap on the expansion tank? Could be wrong? can you remember what your GS is like? Seems odd as the cap on my expansion tank has not got any attachments for a pipe to go onto but have wondered if its been messed about with by previous owner or something.

[ColinBarber]

See attached. Not every easy to see.

[Glenn]

See attached. Not every easy to see.

Thanks for the pic Colin, yep mine is different to that? The small hose going from top of rad to the expansion tank just under the cap is not on mine? I wonder if someone has changed the expansion tank and put a different type on mine as mine has not got a fittment for the small hose to go too? Interesting, would explain the water not able to stay at max level.

[Mike_B]

I will check tomorrow, but i'm pretty sure mine looks the same as Colin's, i.e. it has two small from rad to expansion tank including the tiny one to just under the cap.

It would seem logical that if yours is missing the hose and therefore has an opening straight off the rad, that there is no capacity for pressure in the system. If that is the case, don't let the motor get too hot or it will just boil the moment the water reaches 100C and spit all the coolant out the hole! If someone has changed it, hopefully they sealed up the radiator too...

[ColinBarber]

Does the expansion tank even connect into the cooling system then if the pipe is missing? The pic I posted is from my old Oct 2000 GS430 so I don't expect any component changes between that one and your 2001 model.

The vehicle hasn't had a front end crash and had non OEM parts fitted has it?

[Glenn]

Yes the expansion tank is connected to the cooling system, ie through hose going from bottom of tank. If i squeez the main top coolant hose it does bubble up into expansion tank. I have had car sat ticking over after warmed up and it doesnt get hot or bubble or anything out of the ordinary? also have checked the small outlet on top of rad with no hose attached to it and no sign of water coming out of it? I wonder if its had the rad changed for a none OEM one as you say Colin and been made to fit? It all seems very odd to me anyway? have had car for about 4 weeks now and driven around 800 miles and have probably added about half a litre to the expansion tank. Did a 300 mile round trip last week all on motorway at reasonable speeds and the temp guage didnt budge from the middle all of the journey. The engine oil is nice and clean still and no sign of sludge on the oil filler cap, so hoping its nothing serious like head gasket leaking etc.

[ColinBarber]

I don't think there is a problem with the head. You would see high coolant temperature if that was the case.

Can you take some pictures?

[dave1]

So you have added 0.5 ltr over 800 miles. Has this cured your gurgling noises? Are you still having to add water? If so how much and how often. If it was being lost due to leakage from expansion tank/pipe or via head, you would have lost more than 0.5 ltr over 800 miles/4 weeks. I think the original suspicion of an airlock in the heater matrix is the most likely cause, especially as you can't see any sign of leakage and your oil is clean, and presumably no sign of oil contamination in your coolant.

Make sure also that the strength of your antifreeze/coolant mix is still adequate after adding water.

[Glenn]

Good point about the antifreeze dave, will have to check that. The colour of the coolant is actually a dark brownish colour but it doesnt look like oil in the water so I am guessing that this is the antifreeze in the system? I always thought that if oil was geting into the coolant it makes it go a bit sludgy looking. Hope this is the case. I will try and take a pic of the set up and post it tomorrow to get your opinion's. Thanks for your help and ideas on this by the way. I always expect the worst when it comes to problems with cars and £££££££££'s it could cost.

[dave1]

I always expect the worst when it comes to problems with cars and £££££££££'s it could cost.

Don't we all! Hopefully yours turns out to be something simple.

[rjburfoot]

Had exactly the same problem on my 2000/X GS430 SE which runs on LPG. Wasn't getting warm inside the car / gurgling sounds and the LPG converter was playing up as it wasn't getting hot enough! Quick trip to my friendly garage, a top up of water later (checked when hot) and it's all back to normal. The problem with Lexus is that I don't ever expect it to go wrong, so don't check it very often. I love my Lexus - it's a fab car.

[ColinBarber]

I would recommend using Toyota LLC Red coolant rather than adding water. Stops corrosion and water pump wear etc.

[Glenn]

I would recommend using Toyota LLC Red coolant rather than adding water. Stops corrosion and water pump wear etc.

Thanks Colin I will get some of that, my coolant is like a dark colour at the mo not red? Hope its not oil??

[Mike_B]

Prob not oil - more like the coolant is either old or else a different brand.

Checked mine briefly yesterday, there is definitely a small pipe coming out from the expansion tank just under the cap. However it doesn't actually attach to the radiator, it runs down behind it, more like a drain or an overflow. So maybe not such an issue if your tank is missing the pipe?