A/c problems w/98 vette
Thread Starter
Le Mans Master
Joined: Dec 2002
Posts: 7,981
Likes: 37
From: Piedmont, SC Currently Own: 99 Nassau blue FRC. Previously Owned: 84,95,98 Indy Pace,01 Z06
A/c problems w/98 vette
When the a/c is on it blows out of all the vents(front,feet defroster,etc). It does this ,and stays this way even when you turn the a/c to different modes. When the mode is set to just blow out of the front vents, it blows everywhere therefore taking it a long time to cool you. what could be the problem ? Thanks
Racer
Joined: Jan 2001
Posts: 457
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From: Stockbridge GA
Re: A/c problems w/98 vette (J's 1998 Pace Car)
Sounds like a vacuum leak on or around the HVAC control box. Unfortunately this thing is buried in the dash. Possibly a vacuum line popped loose during service on the radio? Take a look see under the passenger side dash and look for loose hoses or connections.
Also, check for codes just to be sure there is no electrical problem as well.
Post what you find.
Also, check for codes just to be sure there is no electrical problem as well.
Post what you find.
Thread Starter
Le Mans Master
Joined: Dec 2002
Posts: 7,981
Likes: 37
From: Piedmont, SC Currently Own: 99 Nassau blue FRC. Previously Owned: 84,95,98 Indy Pace,01 Z06
Re: A/c problems w/98 vette (Bugster57)
Will this be an obvious thing to find? Will i need to take the dash apart to see this loose connection if thats so.Thanks for all info.
Thread Starter
Le Mans Master
Joined: Dec 2002
Posts: 7,981
Likes: 37
From: Piedmont, SC Currently Own: 99 Nassau blue FRC. Previously Owned: 84,95,98 Indy Pace,01 Z06
Re: A/c problems w/98 vette (Quick Brick)
No , but i do wash the engine and everything around there. Is it possible i hosed it off?
Racer
Joined: Jan 2001
Posts: 457
Likes: 0
From: Stockbridge GA
Re: A/c problems w/98 vette (J's 1998 Pace Car)
Pull the codes, don't tear the dash apart....yet.
I haven't done that and It looks like a real pain to get into.
Look the engine bay over very closely, maybe you do knock off an vacuum hose. Check for loose hoses that aren't connected especially around the intake manifold near the firewall.
Keep it simple, cause we can't fix it if it's hard!
I haven't done that and It looks like a real pain to get into.
Look the engine bay over very closely, maybe you do knock off an vacuum hose. Check for loose hoses that aren't connected especially around the intake manifold near the firewall.
Keep it simple, cause we can't fix it if it's hard!
Thread Starter
Le Mans Master
Joined: Dec 2002
Posts: 7,981
Likes: 37
From: Piedmont, SC Currently Own: 99 Nassau blue FRC. Previously Owned: 84,95,98 Indy Pace,01 Z06
Re: A/c problems w/98 vette (Bugster57)
Well it's not giving any codes at the present although about three weeks ago when i went to the beach the check engine light came on, but nothing seemed to be wrong with the air or anything else . I drove it back home about 250 miles and before i got home the check engine light went off. I checked the codes at that time and if i recall right they were all history codes so i erased them all . But i will check in the areas listed in the replies and see what i can find. thanks alot!!
Pro
Joined: Jul 2002
Posts: 627
Likes: 0
From: Campbell Ca
Re: A/c problems w/98 vette (J's 1998 Pace Car)
Did you ever have the leaky battery issue?? as I recall there are vacuum lines beneath the battery. When you get acid on them they could have gotten eaten up.
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Thread Starter
Le Mans Master
Joined: Dec 2002
Posts: 7,981
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From: Piedmont, SC Currently Own: 99 Nassau blue FRC. Previously Owned: 84,95,98 Indy Pace,01 Z06
Re: A/c problems w/98 vette (lost)
Well, I took the battery out and the battery holder to see if maybe a vacuum line came loose or got eaten up by batt. acid ,but I did not see any vacuum lines there. I did this first because i just put a battery in about week and a half ago and it seemed to all start then. I then looked under the passenger side dash and took the covering off the bottom of the dash but I did not see anything. I have a vacuum/boost gauge in the car and it has normally been reading around 20. It is now reading around 16-17 now since I have this problem. Keep sending the help. THANKS.
Advanced
Joined: Sep 2002
Posts: 91
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From: Abilene TX
Re: A/c problems w/98 vette (J's 1998 Pace Car)
HA HA. I hate this. I actually had this happen to me last week and it should be a simple fix. I swapped out my LS1 intake for an LS6 intake and after I got done you could hear a hissing noise coming from the intake somewhere. We looked around and found that there is a little hose on the back of the intake that was not connected. Well I decided to drive it and find out what the leak effected and sure enough it was the A/C. It blew out every vent no matter what mode it was in. I put the hose back in it's home and BAM no more vacuum leak and the A/C was perfect again.
To check it go to the passenger side of the car and reach around the back side of the intake manifold and it should be right there. It's a real tight fit but you can also see it if you get a flashlight and look.
Good luck :thumbs:
To check it go to the passenger side of the car and reach around the back side of the intake manifold and it should be right there. It's a real tight fit but you can also see it if you get a flashlight and look.
Good luck :thumbs:
Racer
Joined: Jan 2001
Posts: 457
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From: Stockbridge GA
Re: A/c problems w/98 vette (J's 1998 Pace Car)
FYI, the a/c plenum box is behind the radio. It uses dampers that open and close to direct the airflow between windshield, front and feet outlets. The air dampers are operated by vacuum actuators. Possibly a damper is stuck?
You can remove the console and the radio bezel, remove the radio and take a look around looking for loose vacuum lines. Possibly the a/c operator control (vacuum switch) has a loose line. It's not a huge deal to take apart or reassemble. This link details removing the radio if you are interested
https://www.corvetteforum.com/techti...D=87&TopicID=1
You can remove the console and the radio bezel, remove the radio and take a look around looking for loose vacuum lines. Possibly the a/c operator control (vacuum switch) has a loose line. It's not a huge deal to take apart or reassemble. This link details removing the radio if you are interested
https://www.corvetteforum.com/techti...D=87&TopicID=1
Team Owner
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From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
Re: A/c problems w/98 vette (J's 1998 Pace Car)
Well, I took the battery out and the battery holder to see if maybe a vacuum line came loose or got eaten up by batt. acid ,but I did not see any vacuum lines there. I did this first because i just put a battery in about week and a half ago and it seemed to all start then. I then looked under the passenger side dash and took the covering off the bottom of the dash but I did not see anything. I have a vacuum/boost gauge in the car and it has normally been reading around 20. It is now reading around 16-17 now since I have this problem. Keep sending the help. THANKS.
Robert
Team Owner
Joined: Nov 1999
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From: This vette goes to 11 Milford MA
St. Jude Donor '03-'05
Re: A/c problems w/98 vette (LoneStarFRC)
Check out this thread when this happened to my 98. http://forums.corvetteforum.com/zerothread?id=442747
Thread Starter
Le Mans Master
Joined: Dec 2002
Posts: 7,981
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From: Piedmont, SC Currently Own: 99 Nassau blue FRC. Previously Owned: 84,95,98 Indy Pace,01 Z06
Re: A/c problems w/98 vette (Fastguy)
I looked behind the intake on the passenger side and the only lines i see are the pcv line and a manifold line that goes back behind the intake and goes into a dual inlet looking thing. Maybe i'm not looking hard enough at this but i do seem to hear a little air noise from this area. Where exactly is this vacuum line that has something to do with the A/C. Sorry to act like a :_dupe: but i am not that familiar with the C5 . I have had 2 C4's so i know a little about them. Thanks for all the previous info and the soon to come info! Jason
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From: Saint Augustine, FL
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St. Jude Donor '03-'04-'05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15-'16
Re: A/c problems w/98 vette (J's 1998 Pace Car)
Well, I took the battery out and the battery holder to see if maybe a vacuum line came loose or got eaten up by batt. acid ,but I did not see any vacuum lines there. I did this first because i just put a battery in about week and a half ago and it seemed to all start then. I then looked under the passenger side dash and took the covering off the bottom of the dash but I did not see anything. I have a vacuum/boost gauge in the car and it has normally been reading around 20. It is now reading around 16-17 now since I have this problem. Keep sending the help. THANKS.
Thread Starter
Le Mans Master
Joined: Dec 2002
Posts: 7,981
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From: Piedmont, SC Currently Own: 99 Nassau blue FRC. Previously Owned: 84,95,98 Indy Pace,01 Z06
Re: A/c problems w/98 vette (JR_VETTE)
Ok i think i am getting there! I just removed the battery and tray again and also the inside right front tire shield and i saw 2 vacuum lines i looked at it closely and their was a hole in it from acid. I pulled up on the hose real gently and it came up with a rubber or plastic elbow where it had rottened off of something. I then looked at the other line and it also had a hole in it. and i pulled up on it and it came up with a black plastic looking actuator(i don't know) that was split all the way down and very brittle. Could this be the answer!! Do I need to go to the dealership and get one of these plastic things and some vacuum line or does other places sell them. THANKS
Team Owner
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From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
Re: A/c problems w/98 vette (J's 1998 Pace Car)
Sounds like you may have found the source of your problem. If the black plastic cylinder (vacuum reservoir/accumulator) is damaged, then definitely replace it as well as any of the small black plastic vacuum lines. Also there is a small check valve attached to these lines and if it's damaged then replace it as well.
BTW, if you're going to repair only the section of the vacuum lines that are damaged that's fine, just make sure you use 1/8" IDrubber vacuum hose to do it with and not 5/32". You might even want to put a small dab of black silicone on the plastic line before inserting it into the 1/8" rubber hose you use for the splice. Just make sure not to get any silicone into the open end of the plastic vacuum line. HTH
Robert
BTW, if you're going to repair only the section of the vacuum lines that are damaged that's fine, just make sure you use 1/8" IDrubber vacuum hose to do it with and not 5/32". You might even want to put a small dab of black silicone on the plastic line before inserting it into the 1/8" rubber hose you use for the splice. Just make sure not to get any silicone into the open end of the plastic vacuum line. HTH
Robert
Thread Starter
Le Mans Master
Joined: Dec 2002
Posts: 7,981
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From: Piedmont, SC Currently Own: 99 Nassau blue FRC. Previously Owned: 84,95,98 Indy Pace,01 Z06
Re: A/c problems w/98 vette (LoneStarFRC)
Alright now! I just replaced the plastic vacuum lines with rubber ones and bought a new check valve because it was split into. I put all of this back together and i still have the same problem. On the reservoire where the vacuum lines go there are two inlets. One is where the vacuum lines ties into the check valve and it goes into one inlet. Is the other one just there for nothing because i don't see anything that supposed to go to it. This is starting to be a PAIN!!!
Advanced
Joined: Sep 2002
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From: Abilene TX
Re: A/c problems w/98 vette (J's 1998 Pace Car)
I'm telling you if you haven't checked the back of the intake and looked at the little hose then you need to check it. A simple little hose popped out of it's place on mine and caused exactly what you are talking about. I'm not saying it can't be anything else but that is what it was for me.