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In lieu of replacing the upstream oxygen sensors, swap them to see if the code moves or does not move to the other bank. Just a thought
 

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Discussion Starter #22
I'm not an expert with the A/C system, but these are the things I've read about an have seen with what little time I've messed with this stuff. If you have the A/C set that reads low an high psi at the same time, I can tell you that both sides should/will read the same based on ambient temp, an everything is at the same overall temp (as in the morning before the engine an A/C are fired up). With ambient temp of about 70 F the low side would be around 30 to 35 psi. A can of refrigerant will/can be drawn into the system, but works a lot better if the A/C is running If your static (or with A/C running) low side psi reading is a lot higher than above, I think that is an indication of some internal problem within the system.
Do you think my issue could be the ac pressure switch? I’ve been reading and researching some of your other inputs on the forum with similar situations.
 

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It says that IF the A/C pressure switch becomes faulty, it would display some info in the DIC an the HVAC/Radio face plate. I doubt that it is faulty. On your post stating 2 gauges showed low side pressure in the red, it tells me you have to much refridgerent in the system. I think you should bleed off some of it into a rag. See if you can get it to read in the 25 to 45 psi range (based on the current ambient temp). Until you post up the high an low pressures your getting from your A/C system when tested in the morning, as well as what those pressures are when its trying to make cold air, I see no way to assist on that system. If your engine coolant temp is ramping up to 220 deg F an an cycling back an forth, my mind says you have some air trapped in the system.
 

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Discussion Starter #24
Was told by the mechanic today that they’ve gotten the high speed fan to finally kick in but not the low speed. I plan to pick it up tomorrow whether they can fix it or not
 

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Very interesting. Does the coolant temperature gauge readout still fluctuate? Presume the radiator fan is engaging without the air conditioner compressor running, correct?
 

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Discussion Starter #26
There’s no fix. They didn’t charge me anything and just allowed me to come pick it up. When I talked to them they just said they let the car run for awhile and they finally came on. It was only high speed. Ac still doesn’t blow cold. Nothing was done. It literally sat at the shop almost 2 weeks
Very interesting. Does the coolant temperature gauge readout still fluctuate? Presume the radiator fan is engaging without the air conditioner compressor running, correct?
[/
 

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Since you.ve been told that your fans run at high speed (but only high speed) I want to say that your Fan 1 R17 cooling relay has a problem energizing. BUT IF that were true, you would also NOT be able to get that passenger side fan to run at high speed either. IF you think you can do a little T/S (with the ignition off), remove the R17 relay (located in the underhood fuse panel). Then correctly locate the 30 an 87 relay pin sockets in the base of that R17 relay, an jump those 2 positions with a wire or paperclip etc. That setup will/would command both fans to run at the low speed. If both fans now run at low speed, it must have been only the drivers side fan running at high speed (when it did come on for them). I think its more important to verify that both fans will run at the low an high speeds first, before zeroing in the the cause of the failed A/C.
 

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Discussion Starter #28
Since you.ve been told that your fans run at high speed (but only high speed) I want to say that your Fan 1 R17 cooling relay has a problem energizing. BUT IF that were true, you would also NOT be able to get that passenger side fan to run at high speed either. IF you think you can do a little T/S (with the ignition off), remove the R17 relay (located in the underhood fuse panel). Then correctly locate the 30 an 87 relay pin sockets in the base of that R17 relay, an jump those 2 positions with a wire or paperclip etc. That setup will/would command both fans to run at the low speed. If both fans now run at low speed, it must have been only the drivers side fan running at high speed (when it did come on for them). I think its more important to verify that both fans will run at the low an high speeds first, before zeroing in the the cause of the failed A/C.
Ok thanks man. I’m going to try that tomorrow
 

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Discussion Starter #29
Since you.ve been told that your fans run at high speed (but only high speed) I want to say that your Fan 1 R17 cooling relay has a problem energizing. BUT IF that were true, you would also NOT be able to get that passenger side fan to run at high speed either. IF you think you can do a little T/S (with the ignition off), remove the R17 relay (located in the underhood fuse panel). Then correctly locate the 30 an 87 relay pin sockets in the base of that R17 relay, an jump those 2 positions with a wire or paperclip etc. That setup will/would command both fans to run at the low speed. If both fans now run at low speed, it must have been only the drivers side fan running at high speed (when it did come on for them). I think its more important to verify that both fans will run at the low an high speeds first, before zeroing in the the cause of the failed A/C.
I couldn’t wait until tomorrow. I tried that on both fans came on at low speed
 

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Back to square one so to speak. May have been on to something in post #4. Be that as it may, swap relay R17 with another known to be working relay.
 

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Discussion Starter #31
Back to square one so to speak. May have been on to something in post #4. Be that as it may, swap relay R17 with another known to be working relay.
I just went and bought another relay for R17. After starting the car and turning on the ac (although it’s hot air) I still didn’t get any fan action.
 

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Do the fans operate normally while the vehicle is idling? Is the temperature hand stable? Can't believe the shop didn't verify the refrigerant charge. By the way, some aftermarket/generic relays are pretty finicky. Don't ask me how I know.
 

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Discussion Starter #33
Do the fans operate normally while the vehicle is idling? Is the temperature hand stable? Can't believe the shop didn't verify the refrigerant charge. By the way, some aftermarket/generic relays are pretty finicky. Don't ask me how I know.
I didn’t let it get up to temp this evening given that it’s a colder evening tonight I didn’t even attempt it. Temp hand is steady and stable. I got a lifetime warranty on the relay I may try and swap for another if possible.
 

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Discussion Starter #34
Do the fans operate normally while the vehicle is idling? Is the temperature hand stable? Can't believe the shop didn't verify the refrigerant charge. By the way, some aftermarket/generic relays are pretty finicky. Don't ask me how I know.
Would they come on with the auto start?
 

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Discussion Starter #36
Great news for me!! This morning got the O2 sensor replaced so that code is gone (for now). Got the car up to temp and boom the low speed fans kicked in. I’m excited and THANK YOU all who chimed in and helped me with my process. I’m now going to make an appointment for the ac to be put on professional gauges.
 

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Excellent. Truthfully, should have stuck with inital thought of going through the cooling schematic diagram two weeks or so ago. Suggest replacing the other upstream oxygen sensor as well. Are you going to another shop for the air conditioner or the same shop?
 

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Discussion Starter #38
Excellent. Truthfully, should have stuck with inital thought of going through the cooling schematic diagram two weeks or so ago. Suggest replacing the other upstream oxygen sensor as well. Are you going to another shop for the air conditioner or the same shop?
I plan on going to a different shop. If there’s nothing that I can do myself
 

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Not unless you're able to borrow or rent the correct gauges to properly check the refrigerant level.
 

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Discussion Starter #40
Not unless you're able to borrow or rent the correct gauges to properly check the refrigerant level.
I now am all of a sudden as of yesterday hearing a rattle/tumble/ticking type of noise and it’s seemingly coming from the ac compressor. I drove it yesterday throughout the day since I’d been without the car and it’s still fairly cool outside. On average I only drive the car once every week and a half or so. I plan to enjoy it this summer though so I really need to figure out this ac issue
 
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