91LS400LEX

On my 1990 and 1991 LS400, BOTH stayed just below the 1/2 way point. Just slightly above the 3rd line up. lol - the owners manual shows anything below the red zone being the normal range. I dont believe that though. Its may not be causing engine damage just below the red zone, but IMO, its not normal.

Lsportline43

I drove the car again last night and it fluctuated very little. The gauge never goes above the half way point, but it will get very close to half and then come back down. But I don't think the typical person would even notice it.

Just to let everybody know, I use to own an Acura Legend and those are known to have blown headgaskets. This is why I am constantly looking at the temp gauge. Paranoia...

lowKut

iTrader: (3)

On my 1990 the temperature gauge needle would go all the way up right below the red mark. This occur quite frequently, is this something I should be concerned about? What do you guys think is causing this?

This would happen when i just start the car (in warm and cold weather) and at times would remain (below the red mark) while driving for about 10 - 20 minutes then return to the middle.

thanks in advance.

Lsportline43

Sounds like a blown headgasket to me. Or air in the cooling system. So it could be a leak in your system somewhere.

From what I understand the LS400's cooling system is designed to bleed itself of air automatically. So if there is air getting into the system, it will be bled out. This may explain why it will raise and then go back to normal temperature.

LiCelsior

iTrader: (32)

ur thermostat is stuck open Mark.

lowKut

iTrader: (3)

where is the thermostat located? sounds like a simple fix that required to be closed, right?

LiCelsior

iTrader: (32)

http://www.lexls.com/tutorials/cooling/thermostat.html

got some free time this week? finally have some time to do some work, so i can finally put on ur alternator lol.

Thermactor

iTrader: (1)

gahh it's so eaaasy! I wish I lived near there. I'd make $$ fixing up LS400s.

LiCelsior

iTrader: (32)

yup then u can put on my supercharger on fo free

lowKut

iTrader: (3)

Thanks, bud!!
I changed the alternator on the GS myself yesterday.

We can work on the thermostat on the LS... please let me know when you're available to do this?

thanks in advance!!

jkweller

i agree with jim but is been about 40k miles so i would say it wouldnt be a bad idea to swap out ur thermostat cant really tell you i know how it is to drive in 34 degrees i live in hawaii the coldest it get here is 47 and the hottest it get is like 95 so yah

future4oo0

Mine used to register low, but after getting new rims put on the car (which probably has nothing to do with it) it starting registering right above the halfway point, but never goes over that. Should I replace anything, or check anything?

Thanks,
Andrew

LiCelsior

iTrader: (32)

should probably throw in a new thermostat. takes 5 minutes max to replace it.

gqr1c3boi

my 99 w/ 91k miles sits about a needle's width above the middle. I've been told that's not normal, but ever since I bought it w/ 65k, it's always sat there.

NewRoLex

mine sits just above the middle is that normal. Just changed the thermostat with oem one from lexus. Thanks in advance.