mine does not have one
I believe that one is under the car near the gas tank.
Yes, it is located in the intake manifold behind the throtle body.
it should be on the side of the transmission with a black rubber tube from the engine leading to it
In the gas tank. it's best done on a lift. You have to drop the tank and get to the top if it. It's in there. Not an easy job.
in the fuse box
Look at the bottom or rear of the radiator
On my 1990 Buick Regal, I need an 18mm wrench , a 10mm wrench, screwdriver, jack, and a can of brake cleaner
The 1990 Buick LeSabre air conditioner recharge valve can be found on top of the air conditioning compressor. The air conditioner recharge valve will have a blue top.
Could be a bad thermostat or heater core
It's computer controlled. No timing adjustments are possible.
Isn't a heater supposed to blow warm air?