plkdb Posted October 5, 2008 Share Posted October 5, 2008 Hi, I have a 1993 SC400 that anytime I try to use the heater, it only blows cool air. Is there a heater valve somewhere that isnt opening, or is there a problem thats typical to these cars? Thanks! Quote Link to comment Share on other sites More sharing options...
1992LexusOwner Posted October 6, 2008 Share Posted October 6, 2008 The heater valve is on the passenger side of the car. Its mounted by one bolt on the firewall, I think. It has 2 vacuum lines to it. One of the Vacuum lines has a little black plastic valve in between them. Check that first. It may be clogged up. One of the ends has a bigger opening than the other. Also check for a vacuum leak, if theres a very small leak, it will not open, yet blowing cold air, and repalce with a new hose. Also check the 2 heater hoses to see if both of the lines are getting warm. If not, maybe your heater core is stopped up. Is there any amount of antifreeze in the floorbooard? Quote Link to comment Share on other sites More sharing options...
cheriwalker65 Posted October 8, 2008 Share Posted October 8, 2008 The heater valve is on the passenger side of the car. Its mounted by one bolt on the firewall, I think. It has 2 vacuum lines to it. One of the Vacuum lines has a little black plastic valve in between them. Check that first. It may be clogged up. One of the ends has a bigger opening than the other. Also check for a vacuum leak, if theres a very small leak, it will not open, yet blowing cold air, and repalce with a new hose. Also check the 2 heater hoses to see if both of the lines are getting warm. If not, maybe your heater core is stopped up. Is there any amount of antifreeze in the floorbooard? Quote Link to comment Share on other sites More sharing options...
cheriwalker65 Posted October 8, 2008 Share Posted October 8, 2008 Hi, I have an SC300 also with the same problem. Are the 2 years the same as far as the part and location of the valve with the vacuum lines?? And does anyone have the manual that shows the location and a possible picture of this heater valve?? And, If so, would it be possible to upload a copy from the manual to this site???? THANKS VERY MUCH FOR ALL THE VALUABLE HELP Quote Link to comment Share on other sites More sharing options...
UCF3 Posted October 8, 2008 Share Posted October 8, 2008 should be similar. Quote Link to comment Share on other sites More sharing options...
plkdb Posted October 13, 2008 Author Share Posted October 13, 2008 Going to take a look at it all tommorrow. So its the item on the pass side towards the rear with a vaccum diaphragm attached to it? I looked it it quickly tonight and saw that one of the vaccum hoses did have a crack in it, whether its bad enough to leak or not, Iam not sure. Worse case scenario, I was thinkingthat I might be able to throw a zip tie over it for a quick fix, to hold the vaccum bracket arm in. Quote Link to comment Share on other sites More sharing options...
1992LexusOwner Posted October 14, 2008 Share Posted October 14, 2008 Well let me know how it goes. You can get a whole roll of vacuum hoses from AutoZone, O'Reilys, or Advanced for nearly nothing. Make sure you take a piece of your original line in there, to assure you get the right size. I would replace all the lines while you are under there. Not too hard, just do one at a time. I hope the zip tie helps! Quote Link to comment Share on other sites More sharing options...
Psicks Posted October 14, 2008 Share Posted October 14, 2008 I am having the same issue with my '94, going to look into this tonight as well. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.