Buick Century

2000 Buick Century Electrical / Lighting Systems   

Could you tell me how to disconnect the speed sensor and what if anything this will do to the car?

Hello, The speed sensor is located on top of the transaxle, has a connector with just two wires, and is held in place with a single bolt.

You will cause an immediate check engine light when you drive. The cruise control will not work. The computer will not be able to maximize fuel economy and the transmission will not shift properly.

Roger

Which side of the car?

Passenger side. There is a Pink wire and a Yellow wire in the connector.

If you don't find it on top of the transaxle look on the right side where the right axle connects to the trans. It should be in that area.

Roger

O.K., thanks. I'll let you know if I find it.

OK, I'll check in later.

Roger

How do I disconnect the odometer?

I have never done that because it is against the law in my state. Removing the instrument from the cluster for a look would be a first step.

Roger

2000 Buick Century Electrical / Lighting Systems   

How do you disconnect the odometer?

You should not, its an electrical plug on trans, no cable. Disconnecting it will affect drivability

Can you give me the specific details as to where it is and how to disconnect and what it will affect as far as driving the car is concerned? Thank -you David Wells

Because it is electronic, it is either directly, or probably on the lh side of transmission, towards the rear. There will be a large nut on a small plastic housing attached to the trans, A black plug in harness will be attached to it. Because this is how the computer, reads the speed, and adjusts the fuel delivery accordingly, I am sure it will trip a 'check engine' light and corresponding code, and will run poor.And no speedometer operation.

2000 Buick Century Windows / Glass   

none of the power windows will go down. When I push the switch it makes a noise like it is trying to go down but nothing happens. I've tried changing the motor and the control panel but neither works. What can I do??

Was the window regulator bad? If you hear the motor operating but the window will not move this is a tell tale sign of regulator failure (common on Buick's). But... all windows? Did they go one at a time or all at once?

1998 Buick Century Electrical / Lighting Systems Malfunction Happens sometimes When warm 

cooling fans dont come on or come on slow. has po1652 as soft code and will sometimes trip check engine light. turning on a/c activates fans properly.

The codes is for the fan relay circuit. Further information is scarce on this code. Not much to do other than checking wiring or swap a matching relay.

Hello, Have you located the cooling fan relays? Is your engine overheating?

Where did you get the PO1652 code? The code book I have says that is a Generic OBDII code for a Vehicle Speed Sensor.

Do you have a wiring diagram?

Roger

Why did you release the question without even having any dialog with me?

Roger

i guess i wasn't sure how this all works. no offense.
i did replace the 5 pin fan relay and swapped around the other 4 pin cooling relays. they all seem to be working properly. i thought maybe there was another circuit involved that i hadn't thought of. i am down to coolant sensors for ecm input or possibly ecm control voltage output failure. what are your thoughts?

I sure would like to monitor the ECM coolant temperarure input. Do you have gauges or warning lights on your dash?

Does your engine overheat? What engine do you have please, 3.1L ? Do you have access to a scanner (not a code reader)?

Roger

it is the 3.8. tomorrow i will check live data for coolant temp. i just don't know the voltage output to the relay corresponding to the coolant emp sensor.
it does heat up when sitting and it is my belief that it overheated while getting smogged. it did not pass for mil status. this is a customer car. i specialize in german cars so i am not totaly familiar with this make/model. thank you for the help.

The resistance value of the coolant temp sensor is an input to the ECM. The cooling fan should come on at approx 106 degrees celcious. They should switch to high speed at 108 celcious.

I'll look for the voltage values for the cooling fan relays. Do you have access to a wiring diagram? Have you cleared the codes to see what resets?

Roger

i have cleared the codes and the same one po1652 comes on instantly when you do key on. even before running the car. the code description is relay2 short to power or ground but i don't find anything. i am so. cal. and will be looking at her car again this morning. i will use the wiring diagram to do a trace and cotinuity check. thanks for the help.

Do you have a email address or fax number I can send data to? Where to?

I looked in a 1998 Buick Shop Manual for the Century and found no code PO1652 or P1652 listed at all.

Roger

my email is [redacted]

under enhanced codes it show p1652 as a cooling fan 2 short. still have found no shorts. the code always comes back with key on engine off. i am thinking it might be a pcm failure.

I'll get a couple of pages to you.

I restate to you that there is no such code in the 1998 Buick Regal Shop Manual.

Roger

Thank you for confirmation that the info I sent was helpful.

To accept my answer so that I may be paid please click on the "OK TO PAY MECHANIC" button.

I hope you'll try us again.

Thanks,

Roger

1998 Buick Century All Part Groups Chugging When driving Always

First the speedometer isn't working correctly. It fluctuates very rapidly. My thought is that this is affecting the speed sensor or the transmission because it wants to downshift according to where the speed is indicated on the speedometer, not the actual speed of the car.

need to know if speedometer is electrical or cable operated

electrical

replace magnetic sensor on trans

did you find the problem

1998 Buick Century Heating / Cooling System   

Driver's side blows warm air but Passenger side blows cold air when in A/C, Max A/C, etc. Is it HVAC head unit or air control dampers?

Hello, Is this car equipped with dual air? Automatic or manual air?

Look under the dash on the right side for a black box programmer that has two linkage arms. One on top, the other on the bottom of the box. Each linkage arm is operated by an electric motor.

Inspect to see if a link has become disconnected from the motor. If all appears normal a motor may have failed.

Parts may be dealer items or found in salvage.

Roger

I don't see a black box on right hand side. Vehicle is not auto or manual dual A/C...just your normal low end single hot/cold control. Thanks for helping!

All right, plain and simple a/c.

There are seperate temp valve control electronic actuators on the HVAC plenum.

I will email or fax a wiring diagram to you. Just need the address or number to send it to.

Your car may need the left temp valve actuator replaced.

Roger

Sounds great! Thanks so much for your help already...you can e-mail the diagrams to [redacted] . Thanks again.

Email is on the way.

Roger

Thanks...got it. Do you have a diagram showing where in the dash/HVAC the actuators are located?

I do not have a pic showing location of the actuators.

Temperature door actuators should be accessable from under the right side of the dash. Removing the glove box will help.

These actuators should be mounted on the HVAC plenum case. Try to determine the one you want by the color code of the electrical wires in the connectors for the actuators.

Roger

How are you doing with this one? Please advise.

Thanks,

Roger

1997 Buick Century Heating / Cooling System   

blower fan control location and replacement

Hello, Look on the firewall under the hood. About half way accross on the top of the case that the blower motor is mounted on you'll see a module with two electrical connectors. It is bolted down with three screws.

With the key off disconnect the two electrical connectors and remove the three mounting screws. Lift out the module,

Reassemble is reverse order.

Roger

No wires on the engine side of the fire wall. Blower motor is under the glove compartment. Wires come from a block to the motor. Think the speed control is inside the blower housing but don't know how to get it out or replace it.

Does this car have automatic climate control?

I'll try a different data base and get back to you.

Roger

The block that you found near the blower motor will be the power module.

I caution you to check to see how many amps the blower motor draws with the engine running and the fan speed on high after the blower motor has run for one minute. It cannot exceed twenty amps or it will cause the new module to fail.

If twenty amps or more draw is found replace the blower motor too.

Roger

Has this car been fixed? Please update.

Thanks,

Roger

1995 Buick Century Electrical / Lighting Systems  Happens always Always

headlights and electric windows and power locks, radio presets do not work. anti lock light stays on

Look for a burnt fusible link on the starter, near the battery or near the fusebox. Check the master fuses in the fusebox.

1995 Buick Century Ignition System   

When I turn my ignition to start my car the starter engages for a second then stops. New starter, new battery. Wires all cleaned and checked. This problem has been intermittent for years. Now it can be days before I can start it. Once it does start the car will re start until it sits for awhile.

Hello,

Please confirm your key does not have a resistor pellet in it.

This is probably a bad ignition switch.

What does the security/anti-theft dash warning light do when you attempt to start the engine?

No anti theft. The dash lights remain lit like they should, the radio and fan I know turn off when the key is fully turned to engage the starter. Everything seams to work just right. You turn the key all the way and the starter engages and everything else seams correct. The engine turns over a tiny bit, I would guess the flywheel turns maybe a quarter turn and the starter disengages/shuts off. You then have to turn the key all the way off to get it to engage again. If you turn the key just back to the on position and turn it back to start nothing, you have to turn the key all the way off and then try and start and the starter will engage again for a second. Look if you want to call me at [redacted] feel free or give me a number. What are the components to the starting system? As far as I know you have two wires only in the key switch, the rod at the side of the steering column goes to the fancy slide switch/ ignition whatever they call it that controls all the on offs during start. That all seams to be working fine. What is between that switch under the column and the starter?

Oh. I re read everything. The ignition switch was the first thing I had replaced a year or so ago. It did not help the intermittent problem that has gotten really bad now. I changed the battery and the starter a few days ago to no avail. The battery was weak and I thought for sure it had to be the starter. The fact that once the car does happen to start, it then will restart until shut off for awhile kind of counts out the ignition switch. When I replaced the ignition switch I was told that it was probably not the culprit and that made no difference. The car also only has 60k on it. Runs like a top when running. I am just at wits end. Here is the vin if it has any help. 1g4ag55m[redacted] There has to be something very weird out of the ordinary. The car is a rusted out patched up beast at this point and I really can't take it to a shop. Gets into way to much money so I tried this hoping for an answer.

There is no factory anti-theft on the car?

There is also the park/neutral switch. Have you checked this?

I think we can get the answer without spending a lot of money.

Hello, What size engine please?

When the condition is present have you tried starting the engine with the transmission in Neutral? What happens there?

I'll be happy to send you a wiring diagram for the starting system. May I have your email address please?

Roger

1994 Buick Century Electrical / Lighting Systems Malfunction Happens always Always

I recently cleaned the two defrost wiring contacts on the rear window of my 1994 Buick Stations Wagon (4-cylinder, auto). It started to function strangely.

After engine is started, the rear defrost switch would be turned on automatically everytime I step on the break pedal, even in parked position.

During driving, (now that the rear defrost is on after shifting from park to drive with pressing the break pedal), I can sometimes manually turn off the rear defrost switch and sometime the switch would not respond to the turn-off press.

When the rear defrost is on, the cruis set and resume would not function. After manually forcing the rear defrost switch to be turned off, I can set and resume cruise, but the cruise would be turned off when the rear defrost function is turned on.

The rear window has a high-level stop light assmebly which shares sthe grounding contact with the defrost wires on the rear window. This grounding contact (on the passenger side) is checked and seems to be connected to the body fine. The other rear defrost contact (on the driver side) seems to contact the pad on the rear window just fine. The other endof the high-level stop light assembly is connected to the hydralic that holds the rear window glass and is not grounded.

I am confused by why the rear defrost function would interfere with the cruise control functions.

Need your advise on where to look.

Hi,
I have an 88 Century wagon, so I know the design. The brakes and the defog are using the same ground on the back glass. This ground is not working, so voltage is backfeeding to the brake switch or the defog, whichever is turned off at the moment. You will need to adjust/clean the ground contact for the rear glass. You may need to check with at test light or voltmeter to pinpoint exactly where you are losing ground. There should be 0 volts on the ground side.
Dale

I checked the grounding of that contact, it seems to have about 2 homs when the rear gate is closed. When the rear gate is open, the grounding seems to be lost. Is this normal? I noticed that there two wiring tubes go into the rear gate and isn't it (the rear gate) supposed to be grounded alltimes?

I suggest you use a test light or voltmeter. Turn the defogger on and have someone hold the brake on. Connect your to a good body ground, then check voltage to the ground on the glass. If there is more than 1 Volt, keep checking the voltage through each connection back to the body. I expect you will be seeing 12V on the ground line and that the problem is on the glass contacts.
Dale

1994 Buick Century Engine  When repairing 

how to remove heatshield protects evaporator. Need to replace A/C evaporator. Or is it possible to repl. Evap. without removing heatshield. Have located 2 bolts HIDDEN underneath, blocked by crossmembers. Maybe it is necessary to remove/displace crossmembers to access these bolts. But sure looks complicated! I have repl evap. in several other vehicles - nothing like this hard!

Probably should have addressed to "Climate Control" not Exhaust topic...
Have Haynes manual, mentions nothing about 'evaporator removal' maybe cause its too complicated for DIY. I have removed all mtg screws/bolts under hood for evap cover; heater hoses; and 3 bolts under dash. Evap cover 'loose', able to see evap, thru 2" gap at top, but not enuf room to remove Evap.
Thanks, Jwallace

trying again to ensure posted..

Hello, What engine please? 3.1L?

Do you see those "dog bone" braces/links between the upper radiator support and the engine? (The ones that control engine roll when the powertrain twists in the frame from torque.)

Disconnect both of them from the engine only. Notice how one or both of these dog bones has a hole (at the engine end) on the bottom of it? Using a prybar in a suitable location on the engine and from the front of the car, pull the engine toward the radiator rolling it forward until you can stab the original bolt in one of these "bottom" holes in the dog bone so as to hold the engine in a "rolled forward" posture.

That should give you some access to the firewall area of the evaporator case. I've had some so mean I put a floor jack under the front part of the engine cradle and loosened the two front cradle mount bolts and lowered it 2-3" with the jack to get the room I needed.

Any help?,

Roger

Roger, 3.1 L eng. Just looked; there is only one dogbone brace. It has only one set of holes; also there isnt any extra hole on mating part either. So I presume to just remove dogbone, and brace the engine fwd to get access. Concern is that exhaust pipe will prevent rotating the engine enough; and the exhaust bolts are similarily very inaccessible. May have to visit dealer and 'buy' copy of page from service manual. Thanks

All right. I'll regroup and see what I can get for you.
Do you have a FAX number I could send info to? Would a cover sheet be needed?

Back today,

Roger

Roger,
Fax [redacted] ; thanks.

I'll send you what I found in the Mitchell 1 Auto Repair Data Base but I am very disappointed with their writing.

I'll go to the Buick dealer tomorrow and get the shop manual info for you and FAX it along, too. Hang in there.

I'm trying,

Roger

Alrighty then...I received copies out of the Buick dealer's 1994 Century Shop Manual and I have sent them to you by FAX.

Will that do it?

Roger

Roger, thx for the fax. It shows fasteners under evap cover. So if you can, find the PROPER removal procedure for heatshield... as I still need that info!!
I had already removed the heatshield, found those 3 fasteners and removed the evap cover!! Success. There is now easy access to the evap, so I can replace it.
The key was getting the blankedy blank heatshield 2 bolts removed. One was fairly accessible, the other (Dr. side) was mostly hidden by crossmembers. That was the reason for original request - how to remove the heatshield. btw, the engine doesn't rotate even 1/4 inch after removing front dogbone. Would have to remove bottom motor mtg bolts to get it to budge. So I reverted to scrunching around the crossmembers, used wobbly and skinny extension on 3/8 drive. It barely would work. It will be a huge problem to replace heatshield however as the wobbly wont help align the bolts. I will probably end up removing crossmember (which supports transaxle and such) - at least one end. So if you can, find the PROPER removal procedure for heatshield... as I still need that info!!

Ok, I'll see what I can find. I see the shop manual left out instructions for heat shield removal on this task. They must think they know everything...tells me that when the car was in warranty they would not pay a technician for the shield removal. Dirty bears!

Back tomorrow. I have to drive to the city to get this info.

Roger

I went to the Buick dealer service dept. today and we looked at an "A" body car on a lift. (3.1L, same as yours)

Does your car have the brace that is seperate and above above the engine cradle cross-member? The one we looked at has two steel brake lines bolted to this brace and the brace is bolted to the car body.

With this smaller brace removed you should be able to access the heat shield bolts with limited access somewhat improved. The technicians suggest that using tin snips to "slot" the boltholes so that you could start the bolts and then slide the shield into place and then tighten the bolts. Using a small piece of foam rubber or even wheel bearing grease; the bolt can be retained in the socket while you attempt to start it in place on the car.

A second alternative is to support the rear cross-member of the powertrain cradle with a jack, loosen the rear bolts on the cradle and lower the powertrain to gain access to the heatshield mount bolts.

We did not find a "PROPER" procedure in the shop manual addressing the R&R of the evaporator heat shield by itself or in conjunction with another repair procedure at all.

I'll fax some figures/illustrations for reference in case they will help. I find nothing further.

Thanks,

Roger

1994 Buick Century Electrical / Lighting Systems Malfunction When driving 

The battery warning light comes on when engine is started or at low speed (< 60MPH) abd the voltage meter needle points in the middle between the 12 and 18 mark. The battery warning light goes off when the speed is > 70MPH and the voltage meter needle points at the beginning of high-end RED mark - where it had always pointed at before the problem.

I was told that the alternator needs to be replaced. However, I like to know if this indicates a part inside the alternator (brush, circuit module, etc.) is broken, or maybe something else other than the alternator is broken.

Visit your local Autozone or Advance Auto store (there may be others) and they will test your charging system free of charge.

They can perform the service with the engine running, or you can remove the alternator and they can test it off the vehicle. Either way it's free.

If the belt is not spinning the alternator fast enough this could be the problem. Check that the alternator spins freely and the belt tension is okay.

1994 Buick Century Electrical / Lighting Systems   

Tail lights won't turn off

Do the dash lights stay on too? These are normally on when the tail light portion of the headlights are turn on. Try unplugging the headlight switch. If the lights go off the switch is likely bad.

Thank you for your reply. Sadly, after we recharged the battery, we found that the dash lights were not on. Also, on removing the headlight switch, the tail lights stayed on.
All of the lights are working normally. Just the tail lights and license plates stay on. Any more guesses?

Was any work done to the car recently?

Unplug relays one by one (if not labeled) to see if the light will go off.

1993 Buick Century Engine Stalling When driving No pattern

Hi. Could be fuel, engine, transmission problem.
Car was running great. Then it began hesitating a little on acceleration. Then it began stalling when you would accelerate from a stop. Put in Park, restart without problem, and then put it in gear, and engine dies. Engine sounds great, accelerates without difficulty in neutral, park. Doesn't do it when first started, and it isn't 100% consistent. (unless I"m the only one there to push it out of the road.)
The mechanic who has looked at it finds nothing on computer diagnostics. and of course, it is an inconsistent problem and won't reproduce itself when they are looking.
I'm screwed on this one. Paid too much for car to begin with. I hope you are serious about your money back guarantee.
I looked at complaints on a Canadian website. There were two that were very similar. Which reminds me - one possible concurrent event when this started was fuel guage needle bouncing a bit.

Unplug the Vehicle Speed Sensor, The plug is located in engine compartment area, Front of car, drivers side on transaxle. Drive the car and see if the problem continues. (Check engine light will either stay on or come on intermittently while this is unplugged) If this does not solve problem, come back here and explain what if any difference doing this made. This is step one in my two part diagnoses.

1991 Buick Century Fuel System   

my buick 3.3 engine has developed an intermiten miss ive changed plugs and fuel filter,it starts easy,idle is not smooth as should be,main problem symtom is it bucks on acceleration or pulling hill in high gear improves with down shift. mass air sensor has been suggested and pre&post oxygen sensors?

Hello, If you haven't changed the spark plug wires I recommend doing so.

Rough idle may be a vacuum leak.

Roger

1990 Buick Century Heating / Cooling System   Always

Air conditioning doesn't work. I think pump is shot. Can I run it in winter without replacing it, or will that hurt the belt?

As long as the pump isnt frozen and the belt turns on the clutch ok, The belt should be fine.

Not frozen now. Could it freeze up because of not replacing it? Is there anything else that can be damaged by not replacing it until warmer weather?

The AC clutch is like a centrifugal clutch that freewheels when AC is off. The only thing you should be risking is the pump itself which you believe to be shot anyway. So all should be fine.

Turns fine, now, but the shaft on the OTHER end is wobbly. Afraid it could snap off and damage something.

Actually what hubby says is that the BEARINGS are going out. Does that make sense? If so, does that make a difference?

Well its possible to get a shorter serpentine belt and bypass the AC compressor for the winter, Since you have fears over damage beyond bad AC compressor , I would replace or by pass just for your own peace of mind.

Yes somewhat, depending on type of compressor, bearings can be replaced. Which would stop the wobbling. Im not sure the work time required to do that or if a flat rate is charged, And in this instance, its sometimes better to get a whole new compressor.

Thanks much for your time and expertise!

your welcome good luck,

1989 Buick Century Heating / Cooling System  Happens always Always

I have a problem with my blower motor. The only speed it will work on is high. If I select low, medium, or medium high, it does nothing. I have replaced the switch, the blower motor resistor, the relay, and the blower motor itself but still it wants to work on one speed only. I also have a problem with my condensor fan. It never wants to turn on. The fan is good I have tested it, and the relay has been replaced, but still no luck. I had to rig a temporary switch to turn it on for now.

Hello, In order to get going on this I'll need to know which engine you have so I can get the correct wiring schematic.

Thanks,

Roger

v6 3.3liter transverse

3.3L V6, OK, I'll look it up tomorrow and get you some ideas to try.

Thanks,

Roger

KEWL, I'LL BE WAITING.

All right, let's do this!

There are two relays in the right front of the engine compartment. The one with a BRN/WHT, A RED, A LT GREEN/BLK and a BLK/RED wires is to the PUSHER COOLANT FAN MOTOR. The ELECTRONIC CONTROL MODULE (ECM), sends a ground to this relay over the LT GREEN/BLK wire from ECM connector 3 pin F3. The ECM monitors the coolant temperature sensor (top right of engine, left of alternator) for the conditions that call for the pusher fan. If you have power at all times on the RED wire at the relay and power on the BRN/WHT wire at the relay with the key on, it's up to the ECM to ground the relay to run the fan. If the coolant temp. sensor is off, the ECM waits for the correct temp. it may not be getting.

Do you have a test light or a meter to test these and the blower motor circuits for the other problem?

Roger

Ready to check out the blower motor problem?

Roger

yes sir sure do, I do have a test meter. Could the problem be the ECM for both the blower motor and the condensor fan?

No, the ECM does not control the blower motor.

Please be sure the fuse for the HTR-A/C is a good one. Disconnect the blower relay. Then with the key on and the blower fan switch on "LOW", do you have any volts at the DK-BLUE/WHT wire on the connector that plugs into the blower relay? Same question, same wire, for all blower speeds except "HI" speed? What do you read in each test?

Any luck with the condenser fan?

Roger

1987 Buick Century Fuel System   

codes read rich idle lean idle. have replaces fuel pump and filter, iac valve. car still cuts off when put in gear or stoped. serges and stumbles when idling in gear

i assume 3.8 engine rich or lean refers to o2 sensors is there black smoke coming out of exhaust

its a 2.5 put two new o2 sensors in there is no black smoke

check compression on these engines should be 125 and up there is also a map sensor located on breather housing check for vacuum

compression is good car runs great just sometimes acts like there is no fuel....new map sensor was put on and plenty of vacum,.... new fuel pump and filter...what next????????????thanks

does it do this from the start or after it gets warm espeacially at stop signs or lights with jerking

sometimes it waits till warm and other times from a cold start.....when acting up it will idle till you put it in gear then it cuts off or is very slugish you have to feather the gas

check egr valve for vacuum leak

1986 Buick Century Ignition System Won't Start When starting Always

The ignition switch appears to have failed.How do I get into it to replace?

Are you trying to replace the actual ignition switch or the lock cylinder (this is what you put the key in)?

We are trying to replace the lock cylinder.
Bill

Use the following link for instructions. The instructions tell you to remove other parts, instructions for removing these parts are covered in other sections of the repair guide.

http://autozone.com/servlet/UiBroker?ForwardPage=/az/cds/en_us/[redacted] d/80/0f/45/8e/[redacted] d800f458e.jsp