1999 SSEI AC and air flow problem
#11
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True Car Nut
I thought there was a better picture of the area, but I couldn't find it. Here'* one that will give an idea of the lines that go into the firewall between the brake booster, and the blower. However, if you have good vacuum going to the controller, that likely is not the problem.
#12
Thanks for the picture, Archon, and yes, I hooked the vacuum gauge to the side that pulled the vacuum with the engine running and saw in excess of 10". Then I hooked it to the other side and used the vacuum pump to pull a vacuum equal to what I saw the engine pulling and it did not drop at all for several seconds. Think that'* good enough to conclude that there is not a vacuum leak serious enough to be causing the problem?
Marion
Marion
#14
Originally Posted by Echo SSEI
We definitely need to try to diagnose this one carefully, as I would hate to see you invest in a programmer or any other part without investigating and testing the usual causes for each problem. And if it turns out to be the programmer or control unit, then it would sure be great if someone here had one or both that you could borrow for testing purposes or at least if someone already had a used unit they are willing to sell.
The above is your last post on the problem I'm having. Several others have posted since. If you still believe this is a programmer problem, I'm going to order one from Bill for $50. I realize you can't be certain, but your guess is far better than mine. Let me know when you get a chance,
Thanks,
Marion
#15
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Originally Posted by marionh
I'll reread your post and see which lines I need to swap.
Thanks!
Marion
Thanks!
Marion
If you need, I'll dig out the 98 service manual and list the colors for tubing to each vacuum motor. I found that others all worked for me and the one to AC never got vacuum (you can also hold a damp fingertip on the end of the line and feel the vacuum pull up after a few seconds when switching to a mode that uses that vacuum line.
#16
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[quote="imidazol"]
If you need, I'll dig out the 98 service manual and list the colors for tubing to each vacuum motor. I
quote]
Blue is the tubing that goes to the vane that closes to make air come out the dash vents instead of going up and out the defroster.
Orange goes to the recirculate valve right above the gas pedal-note it opens slowly because of a vacuum block in the line.
Green goes to double motor that closes to keep air from coming out the floor when the AC is on.
White goes to the other end -- I forget when it operates.
Originally Posted by marionh
I'll reread your post and see which lines I need to swap.
Thanks!
Marion
Thanks!
Marion
quote]
Blue is the tubing that goes to the vane that closes to make air come out the dash vents instead of going up and out the defroster.
Orange goes to the recirculate valve right above the gas pedal-note it opens slowly because of a vacuum block in the line.
Green goes to double motor that closes to keep air from coming out the floor when the AC is on.
White goes to the other end -- I forget when it operates.
#17
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Originally Posted by marionh
Imidazol,
From the posting I'd read here, the next step was to use a socket to remove 2 nuts, but I did not have anything deep enough to remove the nuts. They are located at the base of what looks like a long stud. I
Thanks!
Marion
From the posting I'd read here, the next step was to use a socket to remove 2 nuts, but I did not have anything deep enough to remove the nuts. They are located at the base of what looks like a long stud. I
Thanks!
Marion
The two screws are just like the ones that hold the glove box to the bottom of the dash-about 1/2 in long, maybe a #8? Ones at the top of programmer and other at the bottom.
The programmer screws into the top and bottom openings on the corner of the heater box.
#18
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Originally Posted by marionh
Echo,
The above is your last post on the problem I'm having. Several others have posted since. If you still believe this is a programmer problem, I'm going to order one from Bill for $50. I realize you can't be certain, but your guess is far better than mine. Let me know when you get a chance,
Thanks,
Marion
The above is your last post on the problem I'm having. Several others have posted since. If you still believe this is a programmer problem, I'm going to order one from Bill for $50. I realize you can't be certain, but your guess is far better than mine. Let me know when you get a chance,
Thanks,
Marion
Usually the issues occur seperately and the fixes are well known. Usually, no cold air = 1) A/C clutch not engaging due to undercharged freon, bad A/C relay, bad compressor or 2) if the clutch engages, then the airmix door actuator gear has usually cracked. Also, I believe the outside ambient air temperature needs to be above 35* F for the compressor clutch to engage. If you can determine weather that the clutch is engaing, then we can focus on the airmix door and programmer. If the clutch does not engage, it could still be the programmer, but at least we know it is probably not the airmix actuator.
Inability to control/select vents = 1) Collapsed nipples 2) vacuum leak along the feed or accessory supply lines.
As far as procedure for daignosis to determine if it is the programer, it usually is by default, by exhausting ALL other paths. Your HVAC system does have codes that it stores to help diagnose faults, but the codes can only be read with a Tech II scan tool (Autozone, Actron, and other handheld scantools cannot read HVAC codes and most computer scantool programs won't either). If you have the digital readout on your automatic air display (the HVAC controller), it should be flashing upon start-up of the car for about 30-45 seconds if you have a problem. If it is flashing and your mechanic has access to a Tech II scantool, he should be able to pull the code(*) that would narrow down the possible problems, maybe even identifying the programmer. Without a Tech II (or having a dealer scan for HVAC codes for about $90) the only way to narrow down the problem is to check each part of the system, one at a time, which is what everybody above has provided or start repalcing parts (which we try to avoid , here to help save people $). Nothing wrong with shot-gunning parts if you can afford it and want to go that way, but we prefer to try to diagnose first.
I know this is frustrating for you since there is no "easy" way for us to tell you it is the programmer, but we can walk you through this the best we can or you can try that programmer, but that is up to you.
Again, I am far from an expert and many here have just as much (and more) experience in this area than I do and they have posted above along with me.
If it was me, I would insure that the compressor clutch is not engaging and many here can help along that path, telling you where to check voltages, and what relays to try swapping. The other item would be to insure freon levels are at spec. If that checks out well, then we would want to look at the airmix actuator door operation to see what it does when you command cold or heat.
As far as the vents, listen under the passenger side of the dash for any "hissing" noises indicating vacuum leak of blockage.
POST EDITED to remove "Lack Of Bonneville Disease" induced comments regarding an Olds 88 that has nothing to do with this post
#19
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Boosty sez I'm slower than Echo, but I'm going to chime in anyway. Before I punted the HVAC progammer over the neighbor'* fence, I'd take a look at the airmix actuator. Pull the glovebox and try to move the airmix door arm manually. If you can move this with little effort, you'll know the gear on the actuator motor is toast and you probably have 2 separate problems (i.e. the HVAC programmer is probably OK). If you can't move the arm manually, your actuator is probably not the issue and you raise the confidence level that your programmer is suspect.
This isn't difficult and will cost you nothing. As the resident tightwad, I should know.
This isn't difficult and will cost you nothing. As the resident tightwad, I should know.
#20
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Good advice Stan (SSE Motorhead). That is what I was trying to say in my long winded reply above....I personally would do all the little checks I could do before getting another programmer, but I, too, am um.....frugal. BTW, Marion, Stan is one of our other experienced HVAC idiots....Um, I mean experts Thanks for jumping on board, Stan. We can use all the help we can get and your not slow, just dial-up limited at times