1998 Buick Century - Answered Questions & Fixed issues

Question edited to fix the murdered spelling :>D please don't type in ALL CAPS. It makes it very hard to read and is considered SHOUTING in Internet Land! Question moved to sub category. Cars of that age has a key for the door with a different keyway and no chip. The ignition key is different and has a chip. To get into the vehicle, get underneath and put a battery charger on the + of the charger on the big red red wire terminal of the starter. Put the - on any clean bolt. Open with the key fob. Move the leads to the battery and charge it up. Then find out why the battery was flat.

Question edited for clarity. See the videos in the link https://www.google.com/search?q=1998+Buick+Century.+Removal+of+sun+visors ..

New sensor for $8 https://www.google.com/search?q=reset+a+low+coolant+light+on+a+1998+Buick+century ..

Sounds like you need to clean the battery terminals again.

Go to autozone.com and go to 'repair info' after typing in your year make and model of vehicle. They have repair guides available and how to guides for repairing domestic and foreign vehicles.

Good luck on finding information on heater repair.

Fuse #23. Here is a diagram. https://www.autogenius.info/buick-century-1998-fuse-box-diagram/

Try this site. If it is not helpful, signup for a free account with Autozone and then search there for a service manual. Buick Workshop Manuals

3800 Coolant elbow replacement YouTube 3.1 L engine is the same .

many fuel pumps get there power from the relay that is energized by the ECM there is a pressure regulator in the system that will report to the ECM to switch on the fuel pump when the pressure falls if you have no power to the relay , it could be because the pressure in the fuel system is above cut in pressure or that pressure regulator is not passing the current to the ECM

Those adapters are barely functional at best. You will never get good sound, even if it was working perfectly. I tried one but then bought an aftermarket stereo.

Do you know how to do automotive electrical testing ? How to use a DVOM - digital volt ohm meter ? You have high resistance in the circuit . Use voltage drop to find the problem . Mastering Voltage Drop Testing with Pete Meier and Jerry Truglia

Compression testing !

code p 0420 refers to cat converter system bank 1---efficiency below threshold====causes ---cat converter---wiring---HO2S (heated oxygen sensor, the one in the exhaust manifold before the cat converter) code p 0300 is random misfires I would suggest changing the HO2S as it reports to the ECM on exhaust content so that the ECM can adjust the air/fuel ratio so it is logical that if that unit is not reporting correctly, the cat converter may be having trouble burning off the gasses correctly The oxygen sensor(O2S) reads the results of the cat converter operation and helps fine tune the ECM settings

Check the Transmission control module first. If it tests OK then look at the shift solenoids inside the transmission

Purchase a Chilton manual for all the diagrams you need.

Should be in the power distribution center under the hood.

check fuses and relay first if good than more than likely---if when u use lever to turn on but wont stay on or dont go on at all would show that the multi switch (inside column ) either broke (plastic) or wore out ---

Under the dash on the left hand side but if there was a wire plug on old seat buckle should be able to loop circuit together so acts like seat belt is always hooked

is it HOT or just not as cold. If its HOT, like heated air, there is a door problem, if its just not cool, the a/c refridgerent is low and will need a recharge, most likely the comp is leaking.

further problems with evap system causing fuel starvation.... try running with evap hose vented to atmosphere.. if solves your problem faulty evap canister.... if not! blocked pipe or faulty evap presser valve