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Bought 1994 LS400 Basket case for $1 Tons of issues. Heat stuck on, Knocking HVAC??
Hi all, Just acquired a 1994 Ls400 for $1. It was non running in a driveway for 4 years and they were going to donate it but I never pass up a free car so I gave it a shot. I have never owned a Lexus before and just had a bunch of BMW's. Got it running and Wow I am impressed with this old school Japanese car! Even with all the issues it has still rides very good and engine is smooth.
The current issue I am woking on is the HVAC system. It had NO freon 134a so I did a full charge and the compressor now comes on. But when you lower the temperature there is a knocking noise form under the dash. I pulled the panel and see that there is an arm that moves when you change the temperature. When the controls set below 80 it seems to bottom out and begins to knock. The cable attached to it came of and Seems really stuck if you try and move it. Does that cable control the air door for the heat? Is there a sensor on the cable or is the servo / arm out of alignment and that is the reason it is clicking? I checked the forums and could not find anything definite. Also what is the name of the factory Lexus Diagnostic software? I have the BMW one and need to get something to diag this, probably a service manual too.
What I did already.
1. Replaced the battery, the one in there was beyond dead, it was corroding out the top.
2. All 4 tires were dry rotted and the rear off the rims and had wheel locks with NO key. Ripped the locks off and got some tires.
3. Had No fuel so added 5 gallons and started right up, but holy hell the smoke! Was like a James bond car!
4. Found the intake was sucking in power steering fluid, so i just plugged the line going into the manifold,
5. Got a full tank a fuel but the gauge read empty and has been slowing going up to about half full. Bad sensor?
read up on the stickies at the beginning of the forum and you will learn MANY fault's on trunk hinge wiring and others... I can tell you have the ability to understand..
Yes. It looks like I already have a few of these faults. Going to tackle the big ones first. I think one of the rear springs are broken as its listing like a sinking ship.
Congrats on the purchase... has to be the record for the best price paid... excluding those that were free for some people. Sounds like your well on your way to bringing her back to life. Have fun and enjoy and yes, they are pretty solid cars.
Yes. It looks like I already have a few of these faults. Going to tackle the big ones first. I think one of the rear springs are broken as its listing like a sinking ship.
I thought that too but this car does not have the extra switch next to the shifter to control the ride height and I believe it has springs but it was dark when I changed the wheel.
Just to show how dirty it was I used the hot water extractor this weekend on the filthy interior and it's way better but still stained. Tried everything but those stains were in there for like 5 years lol.
Oh that is going to be nice.... had an aunt in Queens back in 56.. (I am 81 now)
make sure your Heater control valve is working, you can pull the wire off the tang and work it to be sure in operates.. here is a photo
Ah, was wondering about this rusty valve. The cable is already off, it does move though. Is this what attaches to that servo knocking under the dash? Closed is clockwise or counter clockwise?
That's just the water valve which supplies hot coolant flow to the heater matrix,shouldn't make any difference to the heater servo controls. They do commonly leak.
Just wondering if that control cable to the valve has seized, put the temperature to max cold then max heat and see if it moves,if it doesn't it could be the drive servo trying to move it, locking up and making the noise.
05-25-15, 04:18 PM
Bought 1994 LS400 Basket case for $1 Tons of issues. Heat stuck on, Knocking HVAC??
