TBI Throttle Body Injection discussion and questions. L03/CFI tech and other performance enhancements.

LOUD bang after burnout..

Thread Tools
 
Search this Thread
 
Old 09-25-2009, 05:35 PM
  #1  
Junior Member
Thread Starter
 
jb112303's Avatar
 
Join Date: Sep 2009
Posts: 14
Likes: 0
Received 0 Likes on 0 Posts
Car: 1990 firebird
Engine: 305 tbi (L03)
Transmission: auto
Axle/Gears: stock
LOUD bang after burnout..

i came to a stop sign then i got on it, and then after about 20 feet, towards the end of the burnout i hear a loud bang as if something dropped and hit the ground pretty hard...i have no idea what that was...anyone else experience this? or know what it could have been?
Old 09-25-2009, 05:50 PM
  #2  
Supreme Member

iTrader: (2)
 
TraviZ's Avatar
 
Join Date: Sep 2003
Location: Woodland, CA
Posts: 10,494
Likes: 0
Received 3 Likes on 3 Posts
Car: '02 Z06
Engine: L33 5.7
Transmission: T56
Axle/Gears: Stock IRS
Re: LOUD bang after burnout..

Check your transmission mount. notorious for breaking and when they do, your tailshaft lifts up and hits the body of your car under harder acceleration.
Old 09-25-2009, 07:30 PM
  #3  
Junior Member
Thread Starter
 
jb112303's Avatar
 
Join Date: Sep 2009
Posts: 14
Likes: 0
Received 0 Likes on 0 Posts
Car: 1990 firebird
Engine: 305 tbi (L03)
Transmission: auto
Axle/Gears: stock
Re: LOUD bang after burnout..

Originally Posted by TraviZ
Check your transmission mount. notorious for breaking and when they do, your tailshaft lifts up and hits the body of your car under harder acceleration.
i figured it was that too, until i got on it again and everything was normal, no noises..it was just that one time..kinda weird
Old 09-26-2009, 07:03 AM
  #4  
Member
 
duderjay's Avatar
 
Join Date: May 2008
Location: calgary
Posts: 195
Likes: 0
Received 0 Likes on 0 Posts
Car: 88 iroc z28
Re: LOUD bang after burnout..

dude check the tranny mount, I did the same exact thing. When the mount goes the **** end of the tranny lifts up and hits the floor. I have had it happen in my 87 camaro and my 88 camaro as well.

What yoiu gotta do is get under the car and check jacj the car up and use what ever means to see if the tranny can lift up or inspect the mount really close.

Or go at slow speed revving a bout 2500 rpm let go of the gas and let it coast a few seconds and then hammer the throttle down and listen for the tranny to bang off you floor boards
Old 10-01-2009, 11:06 AM
  #5  
Junior Member
 
helomech's Avatar
 
Join Date: Sep 2009
Posts: 28
Likes: 0
Received 0 Likes on 0 Posts
Re: LOUD bang after burnout..

what's involved in swapping out the tranny mount? I haven't seen the underside of my car yet. Though when I stopped in a turnout on the way up the mountain, I did get a clunk when I took off. If sounded exactly like a broken mount. Only thing I checked when I got home was if the motor would lift off a mount when torqued up a little in D or R with the brakes on.. was solid both directions. Which leaves me to ASSUME that the trans mount is gone.

The dork I got my car from told me "it's really easy to do donuts in this thing"... glad I saved the car from him. When I think donuts, I think mmmmmmmmmm donutssss.... chocolate... filled... powdered... mmmmmm donuts....
Old 10-01-2009, 11:11 AM
  #6  
Moderator

iTrader: (5)
 
JamesC's Avatar
 
Join Date: Aug 1999
Location: Lawrence, KS
Posts: 19,282
Received 93 Likes on 68 Posts
Car: Met. Silver 85 IROC/Sold
Engine: 350 HO Deluxe (350ci/330hp)
Transmission: T-5 (Non-WC)
Axle/Gears: Limited Slip 3.23's
Re: LOUD bang after burnout..

Originally Posted by helomech
what's involved in swapping out the tranny mount?
https://www.thirdgen.org/trannymount

JamesC
Old 10-01-2009, 12:09 PM
  #7  
Junior Member
 
helomech's Avatar
 
Join Date: Sep 2009
Posts: 28
Likes: 0
Received 0 Likes on 0 Posts
Re: LOUD bang after burnout..

Thanks for the link...
Old 10-02-2009, 05:40 PM
  #8  
Member
 
duderjay's Avatar
 
Join Date: May 2008
Location: calgary
Posts: 195
Likes: 0
Received 0 Likes on 0 Posts
Car: 88 iroc z28
Re: LOUD bang after burnout..

The dork I got my car from told me "it's really easy to do donuts in this thing"... glad I saved the car from him. When I think donuts, I think mmmmmmmmmm donutssss.... chocolate... filled... powdered... mmmmmm donuts....[/quote]


Damn not cool to buy a car off a dude like that................

Man I am so glad I got mine from a 50 year old woman, friggin engine oil stays clean and doesnt burn a drop of oil, mint interiour......
Old 10-03-2009, 10:13 PM
  #9  
Junior Member

 
turbosbox's Avatar
 
Join Date: Apr 2006
Location: Northern CA
Posts: 91
Likes: 0
Received 0 Likes on 0 Posts
Car: 88 TPI formula
Engine: L98 Vortech
Transmission: TH700r4
Axle/Gears: 3.27
Re: LOUD bang after burnout..

i did the same thing doing a burnout off a speedbump in my iroc before. i didnt hear it for some time then again later after certain burnouts.
the trans and engine oil tends to get on that rubber mount, combined with pull from that torq transfer bar from the rear end, to rip it apart.
i'd replace it before you mess up a driveshaft or something else.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
UltRoadWarrior9
Tech / General Engine
336
04-28-2020 10:39 PM
92firebirdguy
TBI
59
09-01-2016 07:53 AM
loud91rs
Camaros for Sale
7
10-05-2015 10:05 PM
luvofjah
Engine/Drivetrain/Suspension Parts for Sale
13
09-26-2015 08:28 PM
Mr. Chevy
Engine Swap
0
09-11-2015 06:06 PM



Quick Reply: LOUD bang after burnout..



All times are GMT -5. The time now is 11:48 PM.