Nissan 370Z Forum  

afterfire or backfire?

I recently had an aftermarket CBE installed (less than 30 days ago) and have recently noticed a muffled backfire/afterfire upon deceleration. I never hear it when I am hitting the

Go Back   Nissan 370Z Forum > Nissan 370Z Tech Area > Engine & Drivetrain > Intake/Exhaust


Reply
 
LinkBack Thread Tools Display Modes
Old 12-29-2009, 08:26 PM   #1 (permalink)
Base Member
 
gleonard's Avatar
 
Join Date: Jul 2009
Location: Los Angeles
Posts: 196
Drives: 370z Touring/Spt 6sp
Rep Power: 16
gleonard has a spectacular aura aboutgleonard has a spectacular aura aboutgleonard has a spectacular aura about
Default afterfire or backfire?

I recently had an aftermarket CBE installed (less than 30 days ago) and have recently noticed a muffled backfire/afterfire upon deceleration. I never hear it when I am hitting the throttle, and usually hear it when I let up on the gas to shift gears.

Is this caused by an exhaust leak? is the car running to rich? Is this normal, does anyone else have the same sound?

I contacted the company who I bought the exhaust from (they also did the install) but I haven't heard back from them yet. It's been a few days so I thought I would try to get an opinion from the experts on the forum.

Any help would be greatly appreciated.
__________________
gleonard is offline   Reply With Quote
Old 12-29-2009, 08:45 PM   #2 (permalink)
Base Member
 
gpa7pk's Avatar
 
Join Date: Apr 2009
Location: Texas
Posts: 135
Drives: 1959 Triumph TR3A
Rep Power: 16
gpa7pk is on a distinguished road
Default

subscribed
gpa7pk is offline   Reply With Quote
Old 12-29-2009, 09:00 PM   #3 (permalink)
A True Z Fanatic
 
Join Date: Jun 2009
Location: Jenks, OK
Posts: 2,281
Drives: 370z Touring/Sport
Rep Power: 267
kannibul has a reputation beyond reputekannibul has a reputation beyond reputekannibul has a reputation beyond reputekannibul has a reputation beyond reputekannibul has a reputation beyond reputekannibul has a reputation beyond reputekannibul has a reputation beyond reputekannibul has a reputation beyond reputekannibul has a reputation beyond reputekannibul has a reputation beyond reputekannibul has a reputation beyond repute
Default

Quote:
Originally Posted by gleonard View Post
I recently had an aftermarket CBE installed (less than 30 days ago) and have recently noticed a muffled backfire/afterfire upon deceleration. I never hear it when I am hitting the throttle, and usually hear it when I let up on the gas to shift gears.

Is this caused by an exhaust leak? is the car running to rich? Is this normal, does anyone else have the same sound?

I contacted the company who I bought the exhaust from (they also did the install) but I haven't heard back from them yet. It's been a few days so I thought I would try to get an opinion from the experts on the forum.

Any help would be greatly appreciated.
As far as I understand it, it's a backpressure pop. Most cars do it, just some you never hear it until you have the kind of exhaust that makes it audible.
kannibul is offline   Reply With Quote
Old 12-29-2009, 09:33 PM   #4 (permalink)
The370Z.com Sponsor
 
F.I. Inc.'s Avatar
 
Join Date: Feb 2009
Location: Simi Valley, CA
Posts: 2,989
Drives: 2010 GT-R/2007 F-250
Rep Power: 685
F.I. Inc. has a reputation beyond reputeF.I. Inc. has a reputation beyond reputeF.I. Inc. has a reputation beyond reputeF.I. Inc. has a reputation beyond reputeF.I. Inc. has a reputation beyond reputeF.I. Inc. has a reputation beyond reputeF.I. Inc. has a reputation beyond reputeF.I. Inc. has a reputation beyond reputeF.I. Inc. has a reputation beyond reputeF.I. Inc. has a reputation beyond reputeF.I. Inc. has a reputation beyond repute
Default

Quote:
Originally Posted by gleonard View Post
I recently had an aftermarket CBE installed (less than 30 days ago) and have recently noticed a muffled backfire/afterfire upon deceleration. I never hear it when I am hitting the throttle, and usually hear it when I let up on the gas to shift gears.

Is this caused by an exhaust leak? is the car running to rich? Is this normal, does anyone else have the same sound?

I contacted the company who I bought the exhaust from (they also did the install) but I haven't heard back from them yet. It's been a few days so I thought I would try to get an opinion from the experts on the forum.

Any help would be greatly appreciated.
Hey bud, sorry that I haven't gotten back to you. It has been very hectic since we got back from the long weekend. Since you are local and I did the install, I would like to hear it in person if you have time. It is not common but always a possibility that something could of loosened up. As a matter of fact, I will just give you a call right now...

Thanks, Tony
__________________
Follow us on Facebook: Fast Intentions Inc.
Phone: (805) 522-FAST (3278)
Email: tony@fastintentions.com
www.fastintentions.com
"FUELED BY PASSION"
F.I. Inc. is offline   Reply With Quote
Old 12-29-2009, 09:47 PM   #5 (permalink)
Base Member
 
gleonard's Avatar
 
Join Date: Jul 2009
Location: Los Angeles
Posts: 196
Drives: 370z Touring/Spt 6sp
Rep Power: 16
gleonard has a spectacular aura aboutgleonard has a spectacular aura aboutgleonard has a spectacular aura about
Default

Hey Tony, thanks for getting back to me, I know everyone's busy with the holidays! I may try to swing by after New Years when things aren't so hectic so you can hear what I'm talking about. Like I said, it's not really an alarming sound, just want to make sure it isn't something that I need to worry about.
__________________
gleonard is offline   Reply With Quote
Old 12-29-2009, 11:18 PM   #6 (permalink)
A True Z Fanatic
 
ChrisSlicks's Avatar
 
Join Date: Mar 2009
Location: North East
Posts: 6,203
Drives: 09 370Z Sport M6
Rep Power: 653
ChrisSlicks has a reputation beyond reputeChrisSlicks has a reputation beyond reputeChrisSlicks has a reputation beyond reputeChrisSlicks has a reputation beyond reputeChrisSlicks has a reputation beyond reputeChrisSlicks has a reputation beyond reputeChrisSlicks has a reputation beyond reputeChrisSlicks has a reputation beyond reputeChrisSlicks has a reputation beyond reputeChrisSlicks has a reputation beyond reputeChrisSlicks has a reputation beyond repute
Default

The noise you are talking about is there stock, just very muffled. I like the noise, it sounds cool. How loud is it?
ChrisSlicks is offline   Reply With Quote
Old 12-29-2009, 11:21 PM   #7 (permalink)
blue660r01
Guest
 
Posts: n/a
Default

When I installed TP's a while ago on my 350z it did this every so often. Does this occur frequently or is it a rare occasion?
  Reply With Quote
Old 12-30-2009, 03:55 AM   #8 (permalink)
Base Member
 
gleonard's Avatar
 
Join Date: Jul 2009
Location: Los Angeles
Posts: 196
Drives: 370z Touring/Spt 6sp
Rep Power: 16
gleonard has a spectacular aura aboutgleonard has a spectacular aura aboutgleonard has a spectacular aura about
Default

Quote:
Originally Posted by ChrisSlicks View Post
The noise you are talking about is there stock, just very muffled. I like the noise, it sounds cool. How loud is it?
it's not any louder than the rest of the exhaust note, it just sounds out of place. It goes from a growl to a gurgle back to a growl.
__________________
gleonard is offline   Reply With Quote
Old 12-30-2009, 09:30 AM   #9 (permalink)
Enthusiast Member
 
Rob@Altered's Avatar
 
Join Date: Jul 2009
Location: Gaithersburg
Posts: 282
Drives: 350Z/370Z/GTR/G35
Rep Power: 369
Rob@Altered has a reputation beyond reputeRob@Altered has a reputation beyond reputeRob@Altered has a reputation beyond reputeRob@Altered has a reputation beyond reputeRob@Altered has a reputation beyond reputeRob@Altered has a reputation beyond reputeRob@Altered has a reputation beyond reputeRob@Altered has a reputation beyond reputeRob@Altered has a reputation beyond reputeRob@Altered has a reputation beyond reputeRob@Altered has a reputation beyond repute
Default

Yeah, it sounds like a normal thing that happens with modified exhausts. It happens on my car every once in a while. You only notice it now that your exhaust is modified and is a little bit louder now.
__________________

Altered Atmosphere Motorsports
RobS@alteredatmosphere.com
Rob@Altered is offline   Reply With Quote
Old 12-30-2009, 10:05 AM   #10 (permalink)
A True Z Fanatic
 
m4a1mustang's Avatar
 
Join Date: Feb 2009
Location: Northern VA
Posts: 55,385
Drives: on two wheels
Rep Power: 6962
m4a1mustang has a reputation beyond reputem4a1mustang has a reputation beyond reputem4a1mustang has a reputation beyond reputem4a1mustang has a reputation beyond reputem4a1mustang has a reputation beyond reputem4a1mustang has a reputation beyond reputem4a1mustang has a reputation beyond reputem4a1mustang has a reputation beyond reputem4a1mustang has a reputation beyond reputem4a1mustang has a reputation beyond reputem4a1mustang has a reputation beyond repute
Default

Yeah, that's totally normal. A little popping and gurgling when you are off throttle... sounds mean.
__________________
- Steve
MAZOC Meet Thread
Zs & Coffee - Saturdays at 10AM in Fairfax, VA and Columbia, MD (Click the banner!)
LIKE us on Facebook!
m4a1mustang is offline   Reply With Quote
Old 12-30-2009, 10:11 AM   #11 (permalink)
A True Z Fanatic
 
370Zsteve's Avatar
 
Join Date: Sep 2009
Location: Gold Coast CT
Posts: 10,599
Drives: 2019 Corvette G.S.
Rep Power: 43
370Zsteve has a reputation beyond repute370Zsteve has a reputation beyond repute370Zsteve has a reputation beyond repute370Zsteve has a reputation beyond repute370Zsteve has a reputation beyond repute370Zsteve has a reputation beyond repute370Zsteve has a reputation beyond repute370Zsteve has a reputation beyond repute370Zsteve has a reputation beyond repute370Zsteve has a reputation beyond repute370Zsteve has a reputation beyond repute
Default

Quote:
Originally Posted by kannibul View Post
As far as I understand it, it's a backpressure pop. Most cars do it, just some you never hear it until you have the kind of exhaust that makes it audible.
Exactly.
__________________
SOLD MY Z MARCH 2018 - another Core OG moves on - new ride 2019 Z Corvette Grand Sport - no mods necessary but already have eyes on HFC and intakes LOL IT NEVER ENDS.
370Zsteve is offline   Reply With Quote
Old 12-30-2009, 10:24 AM   #12 (permalink)
A True Z Fanatic
 
spearfish25's Avatar
 
Join Date: Mar 2009
Location: Naples, FL
Posts: 4,117
Drives: to work
Rep Power: 1856
spearfish25 has a reputation beyond reputespearfish25 has a reputation beyond reputespearfish25 has a reputation beyond reputespearfish25 has a reputation beyond reputespearfish25 has a reputation beyond reputespearfish25 has a reputation beyond reputespearfish25 has a reputation beyond reputespearfish25 has a reputation beyond reputespearfish25 has a reputation beyond reputespearfish25 has a reputation beyond reputespearfish25 has a reputation beyond repute
Send a message via AIM to spearfish25
Default

Enjoy the sound...that's my favorite part of any exhaust note. The TopGear guys call it 'runoff'. It's the sweet 'burble' you get when you lift the throttle and decelerate. When I did the muffler delete, it was f'ing awesome.
__________________
2013 Cadillac V-Wagon, RIP Z
spearfish25 is offline   Reply With Quote
Old 12-30-2009, 11:03 AM   #13 (permalink)
Base Member
 
Join Date: Nov 2009
Location: Oak Cliff
Posts: 78
Drives: 09 MB 370 base/sport
Rep Power: 15
darkROAM_1 is on a distinguished road
Default

Heck, when I had my Slowica w/ it's Kazuma exhaust, I got backfires w/ actual visual flame pops. It only happened when hitting on the gas w/ a little load then immediately letting off the gas or pressing in the clutch. Since the car was in the process of accelerating, there was more un-combusted gas in the exhaust that would ignite there.

This is also due to the fact that I was running no cats at the time.
darkROAM_1 is offline   Reply With Quote
Old 12-30-2009, 11:26 AM   #14 (permalink)
Base Member
 
DJ_TJ's Avatar
 
Join Date: Nov 2009
Location: soul cal
Posts: 29
Drives: 09 nismo #0097
Rep Power: 15
DJ_TJ is on a distinguished road
Default

my fc used to shoot flames with racing beat's exhaust because it was running rich and no cats. after getting it tuned no more flames or popping noises.
DJ_TJ is offline   Reply With Quote
Old 12-30-2009, 04:44 PM   #15 (permalink)
A True Z Fanatic
 
Modshack's Avatar
 
Join Date: Mar 2009
Location: Greenville NC
Posts: 2,883
Drives: 370Z Sport
Rep Power: 976
Modshack has a reputation beyond reputeModshack has a reputation beyond reputeModshack has a reputation beyond reputeModshack has a reputation beyond reputeModshack has a reputation beyond reputeModshack has a reputation beyond reputeModshack has a reputation beyond reputeModshack has a reputation beyond reputeModshack has a reputation beyond reputeModshack has a reputation beyond reputeModshack has a reputation beyond repute
Default

Quote:
Originally Posted by spearfish25 View Post
Enjoy the sound...that's my favorite part of any exhaust note. The TopGear guys call it 'runoff'. It's the sweet 'burble' you get when you lift the throttle and decelerate. When I did the muffler delete, it was f'ing awesome.
Ah...The "burble"....Sure wish I had some with the Stillen... I used to love that on my Vette....
__________________

Steal my car! (SOLD)...Now Porsche Cayman S
Oil Cooler DIY: Here!
Modshack is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -5. The time now is 02:23 AM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO 3.6.0 PL2