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Backfiring?

I've posted on here a few times about how I have had a rough idle and I see that some of you have the same issue. My next question is this, has anyone had any issues where the car actually backfired? I have this issue on occasion(usually shortly after startup, when I'm accelerating and then let off to shift). It is definitely a backfire, and is not just the burble of the exhaust, or the pop on the overrun. I actually hear a loud explosion. I'm guessing that the car is running rich? Could this be part of the rough idle issue? Still no CEL. If I take it to the dealer and they don't see any trouble codes, and I'm not able to duplicate the backfire, I'm sure I'm going to hear the same thing I heard when I brought it in for the rough idle(which was pretty much nothing). I have no mods to date, and have the side pipe plate restrictors removed. Any suggestions before I(great) go back to the dealer?
 
The first thing I'd do is reset the PCM. You can do this by disconnecting your battery for 10 minutes. Once you reconnect the battery go drive it for five miles. The idle should smooth out but I'm not sure about the backfire. Also check for vacuum leaks, obvious stuff like your valve cover breather hoses.
 
Bossy1908 said:
I've posted on here a few times about how I have had a rough idle and I see that some of you have the same issue. My next question is this, has anyone had any issues where the car actually backfired? I have this issue on occasion(usually shortly after startup, when I'm accelerating and then let off to shift). It is definitely a backfire, and is not just the burble of the exhaust, or the pop on the overrun. I actually hear a loud explosion. I'm guessing that the car is running rich? Could this be part of the rough idle issue? Still no CEL. If I take it to the dealer and they don't see any trouble codes, and I'm not able to duplicate the backfire, I'm sure I'm going to hear the same thing I heard when I brought it in for the rough idle(which was pretty much nothing). I have no mods to date, and have the side pipe plate restrictors removed. Any suggestions before I(great) go back to the dealer?

When you say "backfire" do you mean through the intake or a pop out the exhaust? Since I removed my stock restrictors and put in the 7/8" ones sometimes I will hear a bang (thud or pop) too. The first time I heard it I thought something hit the side of the car but not to worry it was the exhaust. If it was running rich you'd have a code. On the other hand, if it pops through the intake it's probably a lean or ignition issue but again, you'd have a code. Let us know if they find anything.
 
SilverBolt said:
When you say "backfire" do you mean through the intake or a pop out the exhaust? Since I removed my stock restrictors and put in the 7/8" ones sometimes I will hear a bang (thud or pop) too. The first time I heard it I thought something hit the side of the car but not to worry it was the exhaust. If it was running rich you'd have a code. On the other hand, if it pops through the intake it's probably a lean or ignition issue but again, you'd have a code. Let us know if they find anything.

The backfire is definitely coming from the exhaust, not the intake. When it DOES happen, I usually(not always) get it during the first few minutes of driving. I live in S. Florida so it's not like I'm starting it up and driving away in anything under 65 degrees(brrrrrrrrrr!!!). I always let the car idle for about 2 minutes or so before I start to drive. Rick, I did try the battery disconnect, and the idle does seem a bit smoother.....thanks again. As far as the backfire, it doesn't happen enough for me to think it needs immediate attention, so I'll have it looked into at the next oil change.
 
I can get a pretty loud bang consistently if I engine break for quite a while and allow it to go under 2k, like over 6 seconds, then lightly touch the gas. It is much louder than plain popping from the Roush AB's and baffle removal when decelerating. I just avoid that situation now.
 
WinterSucks said:
I can get a pretty loud bang consistently if I engine break for quite a while and allow it to go under 2k, like over 6 seconds, then lightly touch the gas. It is much louder than plain popping from the Roush AB's and baffle removal when decelerating. I just avoid that situation now.

That sounds like what I get sometimes as well. Maybe that's what you're hearing.
 

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