QuestionQUESTION: Hello,
It has begun to get very very cold here, down to the -14 degree margin which is very unusual which I might add hahah, but my 2000 LHS with the 3.5 V6 starts right up no problems.. However, the heat has stopped blowing hot air... it only blows luke-warm air.. I have flushed the heater core and have found that the previous owner had put some form of stop leak in the system because of the radiator, I have since replaced the radiator and now I have found that the stop leak has clogged the heater core and now I have barely any heat... What do you suggest? is there a known way to purge stop leak from the system completely? or should I just replace the whole core? If it is the core how much time does the job take to do? I know that you have to take the dashboard out but are there any shortcuts to save a little bit of time?
Please Advise
Thanks!
ANSWER: Hi Paul,
I would begin by verifying that it is a flow through problem by touching the two hoses that go to the core at the firewall, after driving the car enough to warm up the engine. If one hose is quite a bit colder than the other then you do have a clog in the core. You could try back flushing the core with a garden hose to drive out the material, after removing both hoses.
If the hoses are similar in temperature then the core is not the problem but rather the blend door that directs the air in vary degrees to either the heater core or the ac/expansion core.
So check first see what the hoses feel like.
Let me know the results of that and we'll go on from there. When you do a follow-up question tell me whether you have the digital readout auto temp control or the conventional temp control panel.
I suspect we can get this resolved with having to remove the core.
Roland
PS Please 'rate' my answer, and where you see the question about nomination for 'volunteer of the month' consider a 'yes' answer. Thank you
---------- FOLLOW-UP ----------
QUESTION: Hi Roland,
It is definitely the core, I have had the car up to full operating temp. and one hose is quite hot and the other one its cooler than the hot one, I have done the heating system diagnostic and it did not bring back any codes so I am assuming all the doors and actuators are working properly
AnswerHi Paul,
I would certainly try the back flushing approach. There may be available an adapter used to flush the cooling system that has a garden hose fitting at one end and that has at the other end a cooling hose nipple fitting so you can get a water-tight seal and put the water through from the cold outlet side of the core and out the hot inlet side of the core. You might try it back and forth a few times.
Changing out the core does require removal of the dash which is a 30-step process in each direction to take out the HVAC unit. Let me know if you want to try that and I can copy the procedure off an '04 CD of the shop manual and email it to you. Use the 'private' option of the question procedure as otherwise the email address is 'blocked' from view. I am going to drop out of availability now but will return tomorrow morning, should you have reached the 'limit' of follow-ups and have to start a new question.
Roland
PS Please rate my answer as I am in competition for expert recognition.
