Generation III External Engine LS1 | LS6 | Bolt-Ons | Intakes | Exhaust | Ignition | Accessories
Sponsored by:
Sponsored by:

Backfire after header install?

Thread Tools
 
Search this Thread
 
Old May 10, 2009 | 08:24 AM
  #1  
Nick_Rapitis's Avatar
Thread Starter
12 Second Club
iTrader: (15)
 
Joined: Jan 2008
Posts: 849
Likes: 0
From: 20 minutes east of Cleveland
Exclamation Backfire after header install?

so i put on my pacesetter long tubes and every now and then it back fires when i rev it or let off the throttle...any ideas/suggestions?
Reply
Old May 10, 2009 | 09:07 AM
  #2  
RAREBIRD17's Avatar
Teching In
 
Joined: Jan 2009
Posts: 5
Likes: 0
Default

Check your plugs/wires.
Reply
Old May 10, 2009 | 10:12 AM
  #3  
Nick_Rapitis's Avatar
Thread Starter
12 Second Club
iTrader: (15)
 
Joined: Jan 2008
Posts: 849
Likes: 0
From: 20 minutes east of Cleveland
Default

Originally Posted by RAREBIRD17
Check your plugs/wires.
ok...check em for what?
Reply
Old May 10, 2009 | 10:21 AM
  #4  
ss_slowmaro's Avatar
Staging Lane
 
Joined: Jan 2009
Posts: 77
Likes: 0
From: Tulsa,OK
Default

Check wires to see if they are fully connected to coil packs and plugs. Take out plugs and check each one for oil or build up( your choice). or it just could be back pressure. its common to backfire a little with no cats when letting of the throttle correct me if im wrong. also what are your plugs gaped at?
Reply
Old May 10, 2009 | 10:25 AM
  #5  
01FbTaWs6's Avatar
11 Second Club
iTrader: (12)
 
Joined: May 2005
Posts: 1,142
Likes: 0
From: Cedar Rapids, IA
Default

i had the same issue, and it ended up being my wires. I had broken then when yanking them off. replaced the plugs/wires and all was good.
Reply
Old May 10, 2009 | 10:25 AM
  #6  
Nick_Rapitis's Avatar
Thread Starter
12 Second Club
iTrader: (15)
 
Joined: Jan 2008
Posts: 849
Likes: 0
From: 20 minutes east of Cleveland
Default

it has cats...well one of the cats got smashed up a bit and lets just say the ceramic insides fell out out...but the car isnt throwing any codes or anything...could a tune with hp tuner software help?
Reply
Old May 10, 2009 | 10:28 AM
  #7  
Nick_Rapitis's Avatar
Thread Starter
12 Second Club
iTrader: (15)
 
Joined: Jan 2008
Posts: 849
Likes: 0
From: 20 minutes east of Cleveland
Default

Originally Posted by 01FbTaWs6
i had the same issue, and it ended up being my wires. I had broken then when yanking them off. replaced the plugs/wires and all was good.
i'll have to check it out tomorrow to make sure...hopefully it isnt the back one cuz i cant reach it for the like of me lol
Reply
Old May 10, 2009 | 10:39 AM
  #8  
ss_slowmaro's Avatar
Staging Lane
 
Joined: Jan 2009
Posts: 77
Likes: 0
From: Tulsa,OK
Default

The # 8 cylinder plug can be reached with mediocre difficulty if you have a jack and jack stands available. jack up the car and reach up to wear the collector for the stock manifold would connect to the cat. its kinda a pain but it beats reaching past the AC and EGR(if you have it).
Reply
Old May 10, 2009 | 10:45 AM
  #9  
Nick_Rapitis's Avatar
Thread Starter
12 Second Club
iTrader: (15)
 
Joined: Jan 2008
Posts: 849
Likes: 0
From: 20 minutes east of Cleveland
Default

Originally Posted by ss_slowmaro
The # 8 cylinder plug cant be reached easily if you have a jack and jack stands available. jack up the car and reach up to wear the collector for the stock manifold would connect to the cat. its kinda a pain but it beats reaching past the AC and EGR(if you have it).
yeah i can get to the plug but not where the wire plugs into the coil pack...arms are to thick lol...it sucks being 6'6" and weighing 250...at least when it comes to working on cars...
Reply
Old May 11, 2009 | 09:37 AM
  #10  
RAREBIRD17's Avatar
Teching In
 
Joined: Jan 2009
Posts: 5
Likes: 0
Default

Is the car actually backfiring or are you just hearing some popping coming from the exhaust when you let off the throttle?

A backfire would sound like a gun is going off and people all around you would be ducking for cover. After I installed headers on my old 88 IROC I messed up the firing order (every wire on my distributor was one terminal off) and it BACKFIRED....yikes!

On the other hand, my Firehawk with a LM2 and stock manifolds pops when I let off the throttle until everything is warmed up.

Steve
Reply
Old May 11, 2009 | 09:54 AM
  #11  
Nick_Rapitis's Avatar
Thread Starter
12 Second Club
iTrader: (15)
 
Joined: Jan 2008
Posts: 849
Likes: 0
From: 20 minutes east of Cleveland
Default

its probably just popping then...i've heard i might just need to change my spark plugs..but i read a horror story on hear about the plugs braking off in the head...that doesnt sound fun at all...
Reply
Old May 11, 2009 | 10:27 AM
  #12  
2000ws6transam's Avatar
TECH Apprentice
iTrader: (5)
 
Joined: Aug 2003
Posts: 350
Likes: 0
From: Cadillac, MI
Default

Im not sure how much just adding headers effects your A/F ratio. But when i did my heads and headers i had bad backfires from running too rich. If you can get it checked for misfires and your A/F at WOT. I took it out yesterday and im still running a bit rich...Someday when i can afford some wide band O2s i will be happy
Reply




All times are GMT -5. The time now is 08:42 PM.