1991 grand prix cruise and a/c problem
gahunter33
07-25-2005, 04:51 PM
I dont know if this information will be of any use because Im not sure if it is related or not so I will start from the beginning......Alternator stopped working, luckily close to an autozone. I tried 3 new alternators in the parking lot and all of them tested ok BEFORE I put them on the car. Everytime I started the car with a new one on, it would go bad in a few seconds according to their machine they test with on the car. Since they didnt have anymore at the store, I had them charge the battery and I drove it a few more miles to the house to work on it further. Once home, the only thing I found odd was that someone had jumped a wire from the ignition fuse under the hood to the drivers side cooling fan. When I checked the fuse it was bad so I replaced it and I also wired the fan back up as it should be. I then went to advance auto this time and bought a new alternator and installed it. Now, FINALLY this one works! and all seemed fine. Now, after I got all happy about it running good again, I hop in for a drive to test it out and I reach over and push the max a/c button and the compressor clicked on under the hood but the air was coming out at the defrost and the floor vents, which btw, it does no matter which button I push. I only left it on for about 30 seconds or so and rode with the windows down until I can figure out whats wrong with it. Also, on this test drive, the cruise control didnt work anymore. Has anyone else had these same problems or might can lead me in a direction to figure this out. I have checked all the fuses in the glove box area and under the hood. Ohh, I almost forgot, I figured out the reason for the fan to be wired to the ignition fuse....If you dont use the a/c, the fans never come on so I assume it was done that way by the previous owner for use during the winter when you dont need a/c but you want the fan to run? I would like to fix that problem also. Sorry this was so long but I wanted to be as detailed as i could.
richtazz
07-26-2005, 01:22 PM
there is a vacuum block near the throttle body that has multiple lines coming off of it. One of them has either come off, or the hard plastic line has split. I believe it is the second one in from the left (as you stand on the drivers side of the car looking down at the throttle body). IF it's still attached at the throttle body , follow it until you find the break and repair it, and your cruise and heater control will start working again.
y2kpa2
07-26-2005, 07:51 PM
did you remove the battery to be charged? the line that runs to the aux vacuum "Ball" under the front of the car runs behind the battery, that line Directly connects to the Cruise-A/C vaccuum line. if that is crushed or broken that will cause loss of vacuum to those systems. remove your battery and inspect that plastic vacuum line. repair or replace even if in doubt and reroute it before replaceing the battery. Had The same problem years ago!
back then my dumbass paid $80 to procare to fix
back then my dumbass paid $80 to procare to fix
gahunter33
07-26-2005, 09:37 PM
Richtazz you beat 88regal to the problem that I was having but man, 88regal, you nailed it exactly as it happened to me. I came home after reading richtazz's reply and I searched all over by the firewall to no avail and then I stepped back and said hey, I took the battery out so let me look there just to be sure and wallah!, when I lifted out the battery, there were three cracks in the vaccuum line. It seemed like a strange place for it to be run thru so I did re-route it before I put the battery in just to be sure it doesnt happen in the future. I appreciate the help!! :smile:
y2kpa2
07-29-2005, 05:47 PM
happy to help!! thanks for the props!
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