Ignition timing issues
Safety Car
Joined: Jan 2004
Posts: 3,783
Likes: 15
From: Northern California
The popping noise is due to the larger diameter headers and 3" exhaust system...The engine also, lacks back pressure.
Perfectly normal, for the mods you have done...
Install the stock exhaust system and the popping will go away.
.
Perfectly normal, for the mods you have done...
Install the stock exhaust system and the popping will go away.
.
Last edited by GKK; May 1, 2014 at 10:21 AM.
Pro
Joined: May 2008
Posts: 670
Likes: 55
"If you are driving a slightly accelerate, then let off the gas, you get a few mild pops out the tail pipes."
That can't be due to a badly adjusted valve, it would pop all the time right. Because you say it is when you let off the gas it makes me think it is timing related. Just a thought. Good luck.
That can't be due to a badly adjusted valve, it would pop all the time right. Because you say it is when you let off the gas it makes me think it is timing related. Just a thought. Good luck.
Melting Slicks
Joined: Jun 2013
Posts: 3,065
Likes: 39
"If you are driving a slightly accelerate, then let off the gas, you get a few mild pops out the tail pipes."
That can't be due to a badly adjusted valve, it would pop all the time right. Because you say it is when you let off the gas it makes me think it is timing related. Just a thought. Good luck.
That can't be due to a badly adjusted valve, it would pop all the time right. Because you say it is when you let off the gas it makes me think it is timing related. Just a thought. Good luck.
Just my 2 cents.
Burning Brakes
Joined: May 2011
Posts: 838
Likes: 2
From: Louisville Ky
I just fixed a misfire on my car, before I fixed it, it was popping out the exhaust on decel. During DFCO, all the cylinders went lean, and the one that was misfiring must not have burned even the tiny bit of fuel that was being injected. This showed up on the AFR gauge along with a popping out the exhaust. Showed 14:1 on the AFR gauge on DFCO.
Just my 2 cents.
Just my 2 cents.
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
DFCO is Deceleration Fuel CutOff, and it really does cut off the injectors completely -- no fuel into the cylinders.
I found out about this when I had a problem and had LEDs hooked up to the injectors. When I backed off the LEDs stopped flashing. Really freaked me out when I first saw it. Then I found out about DFCO...
I found out about this when I had a problem and had LEDs hooked up to the injectors. When I backed off the LEDs stopped flashing. Really freaked me out when I first saw it. Then I found out about DFCO...
