Celsior UCF30/31 Blowing Cold Air / No Heat Issue

[jdmvip]

Hey guys so about a month ago I first noticed an issue where if I was in idle the air wouldn't get hot (this is with a fully warm engine). But then I would drive and everything would be fine and the air would get hot.

Today that changed and even while revving or driving the air doesn't get hot. I've heard it could be the heater core, thermostat or possibly air bubble in the coolant from being low. I haven't checked the coolant level but will later today. I know there must be some in there for sure because the engine temperature registers. The engine also isn't overheating.

If anyone has any ideas please let me know!

[rhdgc8]

Defiantly sounds like a thermostat issue. I would change that before you look into a heater core.

[jdmvip]

Thanks Holly I think it could be too but although I was planning on checking coolant level fate would have it later in the day on Friday that it would check itself .
I was cruising in the hood with my family and suddenly the CEL came on, TRC OFF, VSV Off and what scared me the most is that the "water temp" suddenly had no reading (I was watching it like a hawk for the last several days).

I pulled over and found the following:





The good news is that the engine is OK since I pulled over right away and it never overheated. The pic doesn't show it but the radiator cap is missing the center piece somehow!
I drove and drove and checked the level and it didn't seem to leak from the radiator. I suspect it can't hold pressure because the rad cap is bad.
Now what the scary question is..............where did the center piece go? I hope it didn't into the rad and melt somehow.

The part I mean is missing is the top "center rubber cap" shown below.


I'm hoping that's all it is and that somehow a previous mechanic (maybe in Japan if the coolant was flushed) messed up and somehow broke it? Although if that were the case I would think this probably would have happened way sooner since I've had the car for about 3 years.

[jdmvip]

I'm sure hoping it is not the head but the exhaust doesn't seem to be burning coolant and the oil doesn't look to be mixed with coolant either.

[jdmvip]

So here's what I mean. Does anyone think it is possible the center broke off and fell inside?

It looks like it may be able to fit through

[jdmvip]

Looks like this has happened to other Lexus owners but most claim it cannot pass outside of the tank due to core size.
Now I just need to get a new radiator cap and new coolant.
https://www.my.is/forums/f87/radiato.../topics/547913

http://autolanka.com/forums/topic/16...-radiator-cap/