Preachdave

It's been a while since I checked in, but my LS400 has continued the fall apart. As those who tried to help in the past know, this all began when the heater only blew cold air. Not that uncommon a problem in an older car, so I replaced the thermostat (which has been done twice), all hoses, have cleaned the valve, flushed, burped, and refilled. cleaned out the ENTIRE system. replaced sensors, NO BLOWN fuses or relays, and still nothing. But, as time went on, I began loosing other things. The tilt steering stuck in the up position, the temperature gauge quit, then the speedometer and cruise quit, then both lighters. It seems like every couple of days, another system fails. Believe it or not, the car runs like a top, just nothing works. Again, there are NO BURNED fuses, and all relays have checked out. I replace both temperature sensors in the manifold (sender unit and fan switch) just to be on the safe side. Presently, the dashboard looks skeletonized. I hope I can remember how and where everything goes. I finally threw up my hands and took it to the mechanic I have do some of my work. He refused to work on it after I told him the story. He said, with an older Lexus, he could spend a LONG time and a lot of my money and still not find the exact problem. Of course the dealer wants my whats left of my retirement fund just to look at it. I am running out of ideas. I am up for any suggestions, PLEASE! Thanks for all the suggestions. Of course I've checked all fuses and relays. Gone through the wiring (except in the truck) which I'm going to try next thanks to amcdonal86. Keep the ideas coming. I appreciate anything. Oh by the way, this moring the Overdrive light started flashing on and off. Everything I've done so far, except for the thermostat, hoses, flushing and filling, has come from mechanics.

I've finally got back to the car. I've checked the hoses repeatedly, and they both are extremely hot. I changed the cabin temp sensor, and still no heat. Lets see, I've replaced the thermostat twice, cleaned the heater valve twice, replaced all hoses (plus blew everything out), flushed the system and refilled twice (because I'm clumsy), burped the system I don't know how many times, removed, checked, and replaced all fuses and relays. changed the cabin temp sensor, checked for error codes, and still no heat. I've got the dash in shambles just checking wiring, from what I CAN see, everything on the controls seem to be working ok. SOOOOOOOOOOO I guess I'm going to have to send it in to have it diagnosed. It's snowing here today so driving with NO heat was a bit contrary to good sense. Maybe one day, the problem will be solved. Thanks again for ALL suggestions. Keep'em coming because I've got to wait until I've got the money to send it in, and with it being Christmas, that may be a while. Again, I really do appreciate any and all ideas. THANK YOU!

Thanks again. Where is it located?

I've change the thermostat twice thinking I might have got a bad one. I had that happen once with my chevelle. But it hasn't changed anything. The engine comes up to proper temp with gauge about half-way? Had the same problem. Replaced thermo, bypassed heat control valve...nada. Turned out all I needed was a new cap for the coolant overflow tank. Yes, the engine comes up to temp. And I replaced the overflow cap a couple of weeks ago after reading a forum about that. I really thought that would do it. Anyway, I just came in from sticking a mirror up behind the controls to see if everything is working when I press the controls, and sure enough, everything is working like it should. I really, really, really, appreciate the suggestions. I figure someone will either hit on the problem, or has had it themselves. PLEASE keep any and alll suggestions coming!!!!!! THANKS AGAIN

I've change the thermostat twice thinking I might have got a bad one. I had that happen once with my chevelle. But it hasn't changed anything.

Thanks again. Sorry, my son plays football for the University of Tulsa and we went to the game yesterday. It was good to get away from the car for a day. Anyway, I checked out the heater core when I replaced the hoses, it looked great, but I blew it out anyway and it was clear as can be. The hoses all heat up fine. However something interesting did happen when I was refilling the radiator. I started getting some warm air, NOT HOT, but when I pushed the "auto" button I lost all warm air, and wasn't able to get it back no matter what I did. This happend when I replaced the Heater relay too, when I first started working on this problem. I started getting warm air, then boom, back to cold and couldn't get the warm air back again. Like I said before, I have replaced all hoses, thermostat, fuses, relays, blown out the system, cleaned the heater valve, flushed and refilled, have NO codes showing, and the circulations door is opening and closing just fine. I had another guy tell me he had this same problem and it turned out to be the control cable to the heater valve, so I have disconnected it and have the valve open all the time. I've tried opening it, closing it. halfway, all the way, nothing changes. It almost acts like something electrical, but everything appears to be working. Oh, I did get the bolt out of the water inlet and there was antifreeze clear to the top. That was before I made the BIG MESS with the antifreeze on the garage floor. OOPS! I am intersted in the small water line running from the water inlet to the manifold (I guess). I can't really see for sure where it goes until I take everything off. Anyway, still puzzelled. Thanks again and any suggestions still appreciated.

First of all, Thank you for responding. I'll try anything at this point. I didn't take it out, I tried like crazy to break it loose, but couldn't. I put some liquid wrench on it, and am going to try again tonight. Who knows maybe that might do it. Nothing else has. However, I am noticing a continous antifreeze smell when I get out of the car, but I have not leak. I've been working on this problem every day for almost 3 weeks now, and when I changed the thermostat the second time, the old hose cracked around the clamp and antifreeze leaked all over everything, so it just may be that. This is my daughters car, and I gave her mine to use while I TRY and fix hers. So I have to throw the car together each night so I have a way to get to work in the morning. Anyway, I'll give it a try. Thanks again.

We've got a 94 LS400 which the heater stopped blowing any hot air. First thought, thermostat. I've changed it twice---no change. Next, heater valve, or heater core. NOPE clean as a whistle through and through. Tried the valve manually in case it was broke, nothing again. Flushed and filled. Changed all the hoses. Nothing. Relays, fuses, OK, OK, OK. NO CODES SHOWING. Vent motor is working. I have had almost everything out and checked. ZIPPO. I'll take any ideas before I'm completely gray headed. Thanks!