Running problems after new AC install
Thread Starter
Melting Slicks
Joined: Jan 2005
Posts: 2,658
Likes: 4
From: Clifton Park NY
Running problems after new AC install
This is on my 84
I put in all new AC components, had the system vac'd and filled with freon. Blows extremely cold air!...woohoo!
Now,
at idle and in gear, voltage is dipping to the point where the car stalls. Turn the AC off is runs fine.
Any thoughts whats causing this voltage drop?
I put in all new AC components, had the system vac'd and filled with freon. Blows extremely cold air!...woohoo!
Now,
at idle and in gear, voltage is dipping to the point where the car stalls. Turn the AC off is runs fine.
Any thoughts whats causing this voltage drop?
Le Mans Master
Joined: Apr 2000
Posts: 5,713
Likes: 105
From: Manassas VA
overcharged?
Edit to add, if recharged with 134a vs 12, I think the charge is only 80% of orig. charge. If overcharged it can send liquid freon back to the compressor (slugging it) and this will cause the compressor to basically hydrolock due to the liquid not compressing as a gas would. I believe this could cause a drag on the motor.
Edit to add, if recharged with 134a vs 12, I think the charge is only 80% of orig. charge. If overcharged it can send liquid freon back to the compressor (slugging it) and this will cause the compressor to basically hydrolock due to the liquid not compressing as a gas would. I believe this could cause a drag on the motor.
Last edited by 93 ragtop; Aug 3, 2012 at 11:47 AM.
Thread Starter
Melting Slicks
Joined: Jan 2005
Posts: 2,658
Likes: 4
From: Clifton Park NY
You guys are giving me some good ideas. i'm wondering if its a tune issue. Never had AC before in this. I'm going to hook up the computer and datalog it to see whats changing, hopefully I can find it.
As far as overcharged, I don't think so. All the parts are new and I mean everything. They vac'd it for almost an hour. Before charging they looked up the orginal specs for the 84 and did the conversion calc for the R134A, its 80% btw.
As far as overcharged, I don't think so. All the parts are new and I mean everything. They vac'd it for almost an hour. Before charging they looked up the orginal specs for the 84 and did the conversion calc for the R134A, its 80% btw.
Thread Starter
Melting Slicks
Joined: Jan 2005
Posts: 2,658
Likes: 4
From: Clifton Park NY
Here's something interesting...and its gonna sound stupid!
When A/C is on, my steering becomes real tight..almost sounds like its grinding when going side to side. When the A/C is off is steers normal.
And no I haven't been drinking yet..lol
When A/C is on, my steering becomes real tight..almost sounds like its grinding when going side to side. When the A/C is off is steers normal.
And no I haven't been drinking yet..lol
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Racer
Joined: Sep 2009
Posts: 414
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From: Oxford CT
Is the belt slipping once the AC clutch is engaging?
Melting Slicks
Joined: Aug 2008
Posts: 2,082
Likes: 50
From: Palmdale CA
This sounds like the Compressor is causing a huge load on the serpentine belt, hence...slowing the power steering, and Alternator. Is the belt tight, is the engine RPM slowing
Thread Starter
Melting Slicks
Joined: Jan 2005
Posts: 2,658
Likes: 4
From: Clifton Park NY
What doesn't make sense is why its not dying in idle but in gear it does.
Le Mans Master
Joined: Feb 2005
Posts: 6,479
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From: Clearwater Florida
Le Mans Master
Joined: Apr 2000
Posts: 5,713
Likes: 105
From: Manassas VA
Thread Starter
Melting Slicks
Joined: Jan 2005
Posts: 2,658
Likes: 4
From: Clifton Park NY
I've checked fueling. Blms and WB are consistant all the way thru.
IAC steps increase 65-114, prelimary Map Hi code before stalling but no Check engine light
I see the compressor engaged at idle and I can hear it running, its also blowing the cold air. When in gear I am hearing it still running.
I will have to stop in an ask them if they can test it for being overcharged. I know I'll have these numbers wrong but I think the spec called for 2.8oz or lbs of R12, and 2.2 oz or lbs of R134a
IAC steps increase 65-114, prelimary Map Hi code before stalling but no Check engine light
I see the compressor engaged at idle and I can hear it running, its also blowing the cold air. When in gear I am hearing it still running.
I will have to stop in an ask them if they can test it for being overcharged. I know I'll have these numbers wrong but I think the spec called for 2.8oz or lbs of R12, and 2.2 oz or lbs of R134a
Melting Slicks
Joined: Aug 2008
Posts: 2,082
Likes: 50
From: Palmdale CA
Have you tried rotating the compressor by hand, there should be some resistance but smooth. Your A/C charge numbers seem to be within reason.
You can do a touch test at the pully's after a run, and check if they feel hot, if they slip.. they will get pretty hot.
You can do a touch test at the pully's after a run, and check if they feel hot, if they slip.. they will get pretty hot.
Thread Starter
Melting Slicks
Joined: Jan 2005
Posts: 2,658
Likes: 4
From: Clifton Park NY
The pulley is moving freely. Very smooth.
It was brought to my attention today that because I run a 3200 stall it may be creating enough drag to where its effecting operation while in gear.
Is this possible?
And if so, is it possible to get around this somehow?
It was brought to my attention today that because I run a 3200 stall it may be creating enough drag to where its effecting operation while in gear.
Is this possible?
And if so, is it possible to get around this somehow?
Thread Starter
Melting Slicks
Joined: Jan 2005
Posts: 2,658
Likes: 4
From: Clifton Park NY
Let me add a bit more to this
Ran the car for several min's with the AC on.
Put it into gear....everytime the car started to stall out I tapped the gas pedal and I could keep it running. So I'm thinking this may be a tuning issue.
Compressor was hot to the touch after this but so was the rest of the engine.
Ran the car for several min's with the AC on.
Put it into gear....everytime the car started to stall out I tapped the gas pedal and I could keep it running. So I'm thinking this may be a tuning issue.
Compressor was hot to the touch after this but so was the rest of the engine.
Thread Starter
Melting Slicks
Joined: Jan 2005
Posts: 2,658
Likes: 4
From: Clifton Park NY
Let me add a bit more to this
Ran the car for several min's with the AC on.
Put it into gear....everytime the car started to stall out I tapped the gas pedal and I could keep it running. So I'm thinking this may be a tuning issue.
Compressor was hot to the touch after this but so was the rest of the engine.
Ran the car for several min's with the AC on.
Put it into gear....everytime the car started to stall out I tapped the gas pedal and I could keep it running. So I'm thinking this may be a tuning issue.
Compressor was hot to the touch after this but so was the rest of the engine.
My normal vac has always been 14-15hg
Idle with AC off- 14 hg
Idle with AC on- 12 hg
Idle with AC on and in gear 8hg
To me thats showing the compressor is putting a lot of strain on the engine?
Key off no belt on- I can freely spin the pulley on the compressor
Key on,AC on, no belt- Compressor is much harder to spin but can spin with one hand and feels smooth