Disconnect the battery. Drain the cooling system. Working in the passenger compartment remove the panels from under the dash and the steering column trim cover. Remove center console if you have one. Remove the heater outlet duct and glove box. Remove the heater core cover. Disconnect the heater hoses from the heater core. The hoses and clamps are in the engine compartment on the firewall. You may have to rotate the engine forward and remove fuel lines transmition dipstick tube and the plenum to gain access to these. Remove the heater core.
Could be a bad thermostat or heater core
Isn't a heater supposed to blow warm air?
Disconnect the 1990 Regal battery. Remove the alternator belt. Unhook the wiring from the alternator then unbolt it. Remove and replace the alternator then reconnect the wiring, belt, and reconnect the battery to finish the installation.
It isn't easy. If you want, get a manual on your car from DISCOUNTAUTOREPAIRMANUALS.COM for about $9 and it will show you how.
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
It's computer controlled. No timing adjustments are possible.
The 1990 Buick Century has a timing chain and not a belt. No replacement is necessary.
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very carefully
It is quite simple to replace the turn signal switch on your 1990 Buick LeSabre. The turn signal switch simply plugs in and out.