Last post on Feb 13, 2013 at 7:44 PM
You are in the Pontiac Bonneville
What is this discussion about?
Pontiac Bonneville, Heating / Cooling, Sedan
#170 of 231 98 sse electrical problems/blower motor ?
Jun 29, 2010 (10:24 pm)
i have a 98 sse...and ive been experiencing electrical problems for some time...bout last winter i had no heat due to a bad blower motor moduel... i replaced it with 1 from a junk yard and it was working fine...but i would always hear a kind of vaccum noise coming from the passenger side even when the heat or ac was off...and about a few months ago i noticed that my battery was being drained... ive replaced my battery and my alternator is excellent...i have to unscrew the negative on my battery daily so it doesnt die on me...and i can still hear that vaccum noise...especialy when i rescrew the negative and start my car...does anyone know what the problem may be...i would greatly appreciate any advice possible
#171 of 231 Re: 98 sse electrical problems/blower motor ? [greasemokey]
Jun 30, 2010 (5:39 am)
Is the motor running when you hear the vacuum noise?
Take off the underdash cover and actually listen closer to find the source to see if it's the black tube coming through the firewall to the right.
If it makes the noise without the motor running and with the key on, see if one of the two actuators that are electrical is running. They have a little electric motor that moves the arms to adjust the vents. The top one cracks a gear and the motor might be running trying to adjust. BUT it should turn off when the key goes off because there's no power to it. I'd have to check the factory service manual but I believe that's the case. What happens if you press OFF on the AC controls while it's making the noise?
#172 of 231 Re: 98 sse electrical problems/blower motor ? [imidazol97]
Jun 30, 2010 (3:05 pm)
when i press the off button it goes off...but i can still hear the vaccum noise...i have the electronic temp control so when i start my car it flashes on and off...and when i turn my car off to run into a store or something and come right back..when i start my car i hear the vaccum noise_my temp control is flashing_and my battery is some what drained...just might have to pay that $85 per hr to see what the problem is...damn
#173 of 231 98 SLE ac issue digital control
Jul 09, 2010 (2:08 pm)
Got 98 bonneville digital ac controls and ac works but air comes out only two places--windshield and floor. Changed dash control and vac programer and still same issue. Any ideas???? Is there a default and air comes top and bottom and no where else when there is a problem in the system?
Thanks for any help!!!
#174 of 231 Re: 98 SLE ac issue digital control [nocargtx]
Jul 10, 2010 (5:30 am)
Let me remind others to diagnose the problem before replacing parts.
Three possible problems:
Bad electric controls from dash controls?
Bad plastic connector on programmer box?
No vacuum from under hood?
The default for no vacuum is that the doors in the heater box are left in defrost mode (which bleeds some air to the floor) so the windshield can be cleared for safety.
There is a common problem with the plastic connector on the corner of the programmer in cars of your era. The plastic softens and sucks shut when vacuum goes through each of the 5 little tubes. There was a black plastic nipple inside the connector that is often blamed.
Bypassing that connector with little tubes to carry the vacuum from the internal plastic tubes to the external ones (different colors in some cases) will fix the problem.
I have read a couple people with no vacuum from under the hood. The plastic tubing starts next to the big brake booster hose on the back of the upper intake manifold. There are soft rubber connectors, people said, connecting the hard plastic tube. The soft rubber vacuum hoses can deteriorate after 10-12 years of heat and aging. Check the connectors for cracks, hardness, or holes. There will be connectors at the upper intake, at the T just in front of the accumulator for the AC (take off the relay cover over the MaxiFuse center), and at the connector on the reservoir under the fender in front of the passenger tire. Check that cannister for cracks. If you pull of the hose, then reconnect and run the motor, removing the hose should give you a good whoosh as air rushes in to fill the vacuum.
If the AC control is bad, most people say it just is obviously dead or crazy.
My testing for vacuum, was run the engine, then turn it off and leave the key ON. Switch between various settings on the control panel. After a few seconds you'll hear the vacuum diaphgrams sucking in to move the doors. Also you can remove the hush panel on the driver's side, and when you switch the controls, you can feel the vacuum diaphgram move with your fingers on the engine side of the diaphragm. The back of it is open so you can feel whether the thing moved. You'll have vacuum for about only 30 seconds or this if your hoses under the hood are all okay.
There are 3 vacuum motors. One above the accelerator slowly closes to give recirculated air taken in from above the driver's feet.
One closes off the floor opening and forces air upward to the dash or defroster openings. This one also has a second vacuum tube. When these are working, it leaves the floor vent partly open for windshield and floor with lots of air to the floor but air going out the defroster.
The remaining vacuum motor operates a horizontal axis door that closes off the flow to the defrosters; this forces the air out the dash vents because the floor vent is supposed to be closed off.
To verify that the blue hose to the defroster door was getting vacuum, I switched the hose to another vacuum diaphragm and felt that motor move closed when AC dash was asked for.
#175 of 231 Re: 98 SLE ac issue digital control [imidazol97]
Jul 10, 2010 (11:59 am)
Thanks for your reply--have changed some elements mentioned and also have vac to the junction connector. Did not check to see if connector was open. I have no vac coming out any of the other tubes to the various actuators on the main box. I only know my source of vac to the connector from outside is good and open.
My main programer box was replaced last year--the lever plastic gears were stripped--it works fine now. Temp changes from cool to hot as it should. My temp light fashes since replacing vac programer.????
#176 of 231 Re: 98 SLE ac issue digital control [nocargtx]
Jul 10, 2010 (12:32 pm)
> only know my source of vac to the connector from outside is good and open.
TAke a long piece of plastic tubing or rubber vacuum tubing. Connect it to the black incoming vacuum and connect it to the blue tube's connector for the dash vents. See if it will pull that diaphgram closed. That would check for full vacuum power in the black line going to the programmer box.
I know of one person who said they were able to get the plastic coupler apart and open up the holes successfully. I would just jumper it with tubing from inside to outside.
The only odd thing is you're getting none of the vacuum motors to work.
Does your car have a separate electrical actuator on top of the HVAC for the passenger side air blend door? Is that motor stripped or not working? Is it plugged into the main programmer box?
#177 of 231 ac digital control issue
Jul 10, 2010 (1:17 pm)
My car does not have a seperate act. for passinger side--has one program box with act arm at top of box and it works OK as best I can tell. Temp goes up and box switches and goes other way and temp changes.
#178 of 231 Re: ac digital control issue [nocargtx]
Aug 16, 2010 (5:41 pm)
Fixed the dern thing--cut vac lines on the two part connector and connected them with small black hose to by pass factory connection and everything fine--works like it should. Apparently the connector does not seal tight enough for vac not to leak.
Wife has cold air like it should be and life is better!!!!
#179 of 231 Re: Drivers side NOT COLD [imidazol97]
Aug 17, 2010 (11:23 am)
Could you please provide me a graphic of this because I need to check and probably change one or more of the actuators. IT would be of great help.