exhaust popping/backfire
07-26-2009, 12:41 AM
#1
Thread Starter
Join Date: May 2008
Location: NV
Posts: 46
exhaust popping/backfire
Having issues with popping sound in exhaust
. It will back fire sometimes when you rev it up and let off gas. I check plugs and they look good. Had friend put rags over tailpipes and I checked for leaks and there were no major leaks. I thought that my offroad pipe might be doing it, but I replaced it with stock pipe with cats and it still does it. What could be causing this and how can I fix it?
Stock motor with larger injectors for TT. This happens when the car is not under boost...
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. It will back fire sometimes when you rev it up and let off gas. I check plugs and they look good. Had friend put rags over tailpipes and I checked for leaks and there were no major leaks. I thought that my offroad pipe might be doing it, but I replaced it with stock pipe with cats and it still does it. What could be causing this and how can I fix it?Stock motor with larger injectors for TT. This happens when the car is not under boost...
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07-26-2009, 08:04 PM
#2
1st Gear Member
Join Date: Sep 2007
Location: Texas
Posts: 99
Has the popping been there since the installation of the turbo or did it start later? Most mustangs even with the stock exhaust will pop when you depress the clutch and let your foot of the gas when the car is cold. Other than that you may need to check your air/fuel ratio.
07-26-2009, 11:19 PM
#3
Thread Starter
Join Date: May 2008
Location: NV
Posts: 46
It's like a stumble lunge forward/miss thing. I had off-road hipe pipe on and was having trouble with low end power. Just put the cats back on and it is still there. No sure what the tune does for low end non boost rpms. I checked the plugs and they were all good. The 02 sensors and timing is jumping alot at idle. Sensors only had 940 org miles and are given ready. It acts like it is constantly trying to adjust. It is driving me nuts.
07-27-2009, 01:41 AM
#4
1st Gear Member
Join Date: Sep 2007
Location: Texas
Posts: 99
It sounds like you are having more issues than just popping. Who did the work on your car? You may want to take it back. What does the car use to increase fuel under boost? If it uses some type of BAP or FMU device then maybe one of these is faulty. You may also have a leak on the turbo plumbing somewhere. The air meter is seeing something at the inlet and the appropriate fuel is being delivered but if there is a leak somewhere a rich condition will occur. The extra fuel plus the higher exhaust temps seen in a turbocharged car will result in backfiring.
07-28-2009, 09:13 PM
#5
Join Date: Jun 2009
Location: MO
Posts: 42
I have a Bullitt CAI and Brenspeed tune. My 09 GT seems to "pop" after I am on it and let off of the gas. It is hard to explain, it almost sounds like a backfire, but not so loud. Is this the air mixture and is it "normal"?
Anyone ?
JR
Anyone ?
JR
07-29-2009, 01:48 AM
#9
Multi-Tasking Moderator!
Join Date: Nov 2006
Location: Detroit Rock City!
Posts: 15,618
When you had the O/R H-pipe did you leave the O2 sensors in? Were they shut off in the back? I am thinking that they are fouled and not reading the A/F ratio correctly. Just throwing that out there and thinking while typing. Let us know what happens and I would get it to a dyno or datalog the stang and get the info to an exp tuner!
