your heater core is no good. There is two water hoses on the inside firewall you need to switch both of those hoses with each other. One is an inlet hose which allows the water to come in and the other is a return. This will fix for awhile but you will need to replace the heater core before winter. Because with these hoses switched you will not have any heat. The heater core in located outside under the hood on the back firewall. For GMC/Sub/Thaos/Yukons: I have a 2002 Sub with the same issues. I striped to trouble shoot it. Come to find out it was the REAR A/C drainage line was clogged. Underneath your car...the plug can be found behind the rear right tire on the cargo floor. Easy fix took a month, the hardest was removing all the seat, rugs and mats!
yes..it is in the trunk on the drivers side behind the carpet
Under drivers seat,under carpet.
should be in the trunk on the drivers side, behind carpet.
Underneath the drivers side seat, under the carpet.
Inside the trunk on the drivers side behind the carpet.
Two quality brands that produce carpet cleaners as well as vacuums are Bissel and Hoover. When shopping for a used cleaner, make sure to look for the cleanest, least-worn brushes and make sure the machine isn't clogged.
it could be your A/C condensation leaking back in, the drain line might be clogged
It's under the drivers seat BUT there is a cover that has 3 bolts two are under the carpet between the two bolts holding the drivers seat favoring the left side more. the other is on top under the carpet too. There is no really good access to these FREAKING bolts due to the carpet. The bolts are 12mm. and it is MUCH EASIER TO JUST REMOVE THE DRIVERS SEAT. That is 13mm. Just look at the E.C.M. and look toward the back in that hole. It is hard to see.
On a right hand drive car the battery is located under the carpet in the drivers footwell
in the trunk on the drivers side under the carpet
You have to remove the drivers seat and pull up the carpet.
Heater Core for sure. Get this replaced and you will have no more problems.