In Dash Rattle......uuugh!!
Thread Starter
Racer
Joined: Dec 2004
Posts: 455
Likes: 11
From: Clovis CA
In Dash Rattle......uuugh!!
98 A4. I have a rattle in the dash, sounds kind of 'deep' and centered, but not right behind the radio or heater controls. It started a couple of months ago and around the same time, the heater stopped blowing hot air.
I just did the dim hvac display fix and while it was apart, couldn't see anything loose.
It may be further back in the dash. Are there any vacuum check valves or anything back there that could be rattling? It seems like since both happened at the same time, (rattle beginning, heater not blowing hot air) that they would be simptoms of the same problem.
How do I get access back there? When I had the radio and hvac controls out, there were metal brackets that everything bolted into and I couldn't see behind them.
Any help?
I just did the dim hvac display fix and while it was apart, couldn't see anything loose.
It may be further back in the dash. Are there any vacuum check valves or anything back there that could be rattling? It seems like since both happened at the same time, (rattle beginning, heater not blowing hot air) that they would be simptoms of the same problem.
How do I get access back there? When I had the radio and hvac controls out, there were metal brackets that everything bolted into and I couldn't see behind them.
Any help?
Melting Slicks
Joined: Aug 2003
Posts: 2,786
Likes: 7
From: Iowa
I do! on rare occasions. first started after a 30 minute drive down a cobblestone road. it only happens from time to time, but it is annoying. I have no idea what's causing it, I haven't taken anything apart yet. let me know if you ever figure it out!
Le Mans Master
Joined: Jul 2004
Posts: 7,727
Likes: 7
From: Twilight zone
St. Jude Donor '05-'06
I have one too.It started conveniently enough just after this last smog check.I have a hunch it has to do with the obdII port in some way he plugged into.It only happens when car is cold.
With my neck in the shape it is in right now,I haven't got in there to take a good look.
Rattles can be a great source of anguish
I wish I could be of more help,but you are not alone...
With my neck in the shape it is in right now,I haven't got in there to take a good look.
Rattles can be a great source of anguish
I wish I could be of more help,but you are not alone...
Thread Starter
Racer
Joined: Dec 2004
Posts: 455
Likes: 11
From: Clovis CA
well, i was hoping someone had done something about this on thier car already.
i guess i'll have to tear it down when the weather warms a little. once i start driving it regularly again it'll drive me nuts.
i guess i'll have to tear it down when the weather warms a little. once i start driving it regularly again it'll drive me nuts.
Le Mans Master
Joined: Jul 2004
Posts: 7,727
Likes: 7
From: Twilight zone
St. Jude Donor '05-'06
Just a heads up,which may help,but there is a section in the 3 volume shop manual dedicated to squeeks and rattles I stumbled across at one time.
If you have them,maybe that is a good place to start
If you have them,maybe that is a good place to start
Team Owner
Joined: Mar 2007
Posts: 35,149
Likes: 2,101
From: Right Corner Pocket of Illinois
No-IL Events Coordinator
2026 Corvette of the Year Finalist - Unmodified
2025 C6 of the Year Winner - Unmodified
2020 C6 of the Year Finalist - Unmodified
2020 Corvette of the Year Finalist (appearance mods)
2019 C6 of Year Winner (appearance mods)
2018 C6 of Year Finalist
St. Jude Donor '12 thru '26
I had a rattle in my dash so I sold my Pontiac. Now I have a buzz in my dash but I need my Ford for daily drivin'! 
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
Intermediate
Joined: Jul 2007
Posts: 29
Likes: 0
From: San Antonio Tx
I just purchased a 99 about two months ago. A few weeks and few thousand miles later I started hearing a really painful rattle...right behind the dash..only happened under load when in drive. I could never re-produce it while in a position to find it. I took it to the dealer on Monday and they checked it out..the noise doesn't happen all the time so naturally they didn't hear it and I travel alot so I couldn't be there to drive it for them. However, they did find that my o2 sensors were not hooked up (meaning not in the exhaust). They were out and resting on the exhaust with empty o2 extensions in their place. Creating a exhaust leak. I had a couple of other exhaust leaks also. I had them repair this and will pick up the car tomorrow. I hope that was my "rattle" noise. God let it have been my rattle noise. And, can someone please tell me why in the world anyone would leave the o2 sensors off???? That concerns me. It's such a strange thing to do.
Heel & Toe
Joined: Aug 2005
Posts: 16
Likes: 0
From: North Tustin Ca
Rattle
I had what I thought was a rattle coming from the dash in my 02 vert. Finally foung the source was the hood on the passenger side was not resting against the rubber stop up by the windshield. Raised the rubber stop up about one turn and presto, no rattle.
Melting Slicks
Joined: Dec 2003
Posts: 3,315
Likes: 17
From: Near Jacksonville Fl.
Don't laugh just go and try this, next time it's cold and the rattle is present.
Reach up and grab your driver sunvisor and hold the mirror door down.
I think you will be suprised, I had my 98 coupe into the dealer more time then I could count for this.
They never found the problem because they always checked it after it sat inside long enough to warm up the plastic.
Reach up and grab your driver sunvisor and hold the mirror door down.
I think you will be suprised, I had my 98 coupe into the dealer more time then I could count for this.
They never found the problem because they always checked it after it sat inside long enough to warm up the plastic.
Thread Starter
Racer
Joined: Dec 2004
Posts: 455
Likes: 11
From: Clovis CA
well it's definately inside the car. and it happens whether its hot, cold, warm, freezing....don't matter. the best way to describe it is that it sounds similar to the fob hitting against the dash...and NO that isn't it. also, the hvac doesn't blow hot or warm air. i'm thinking it has something to do with the vents towards the fire wall??
it is as annoying as my ex.
it is as annoying as my ex.
Le Mans Master
Joined: Jul 2004
Posts: 7,727
Likes: 7
From: Twilight zone
St. Jude Donor '05-'06
I have to agree about the hood rattle,it sounded like it was inside too.A minor adjustment fixed that rattle.
Then I also remembered,that at one point,I had developed a rattle that turned out to be just the visor not being firmly in the mount.I know it sounds kind of dumb,but it projected and sounded like it was in the dash.It troubled me for a little while
Probably not your issue,but since many may look here that have a rattle,....well, why not?
So,I'm 2 down,1 to go
Then I also remembered,that at one point,I had developed a rattle that turned out to be just the visor not being firmly in the mount.I know it sounds kind of dumb,but it projected and sounded like it was in the dash.It troubled me for a little while
Probably not your issue,but since many may look here that have a rattle,....well, why not?
So,I'm 2 down,1 to go
Le Mans Master
Joined: Jul 2004
Posts: 7,727
Likes: 7
From: Twilight zone
St. Jude Donor '05-'06
Looked in manual,here is what I found pertaining to rattles in dash:
Rattle from center of instument panel(I/P)
Possible cause
The I/P pad attaching screws at center defroster vent are loose
Correction
1. Road test while applying pressure to the vent area of the I/P pad and listen for the noise to stop
2.Remove the center defroster vent and tighten the I/P pad attachment screws
3. Reinstall vent
Rattle from the forward outer edge of the Instrument panel pad
Possible Cause
Not enough insulator foam between the I/P and the pad.
Correction
1. Road test and apply hand pressure to the forward edge of the instument panel pad to find the location of the rattle.
2.Remove instrument panel pad.
3. Install added insulation at the point of rattle to the underside of the pad.
May not be your cause,but I hope it may help in some way.
Rattle from center of instument panel(I/P)
Possible cause
The I/P pad attaching screws at center defroster vent are loose
Correction
1. Road test while applying pressure to the vent area of the I/P pad and listen for the noise to stop
2.Remove the center defroster vent and tighten the I/P pad attachment screws
3. Reinstall vent
Rattle from the forward outer edge of the Instrument panel pad
Possible Cause
Not enough insulator foam between the I/P and the pad.
Correction
1. Road test and apply hand pressure to the forward edge of the instument panel pad to find the location of the rattle.
2.Remove instrument panel pad.
3. Install added insulation at the point of rattle to the underside of the pad.
May not be your cause,but I hope it may help in some way.
Last edited by flynbya2; Jan 17, 2008 at 08:36 PM.
Instructor
Joined: Jan 2003
Posts: 226
Likes: 0
From: debary fl
98 A4. I have a rattle in the dash, sounds kind of 'deep' and centered, but not right behind the radio or heater controls. It started a couple of months ago and around the same time, the heater stopped blowing hot air.
I just did the dim hvac display fix and while it was apart, couldn't see anything loose.
It may be further back in the dash. Are there any vacuum check valves or anything back there that could be rattling? It seems like since both happened at the same time, (rattle beginning, heater not blowing hot air) that they would be simptoms of the same problem.
How do I get access back there? When I had the radio and hvac controls out, there were metal brackets that everything bolted into and I couldn't see behind them.
Any help?
I just did the dim hvac display fix and while it was apart, couldn't see anything loose.
It may be further back in the dash. Are there any vacuum check valves or anything back there that could be rattling? It seems like since both happened at the same time, (rattle beginning, heater not blowing hot air) that they would be simptoms of the same problem.
How do I get access back there? When I had the radio and hvac controls out, there were metal brackets that everything bolted into and I couldn't see behind them.
Any help?
