Aftermarket header problems
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Joined: Apr 2014
Posts: 206
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From: Miami, FL
Aftermarket header problems
So after installing an aftermarket header my car is burning extremely rich and i have no idea how to fix it i mean if i replace the sensors assuming they arent working wouldnt they get the same reading and not fix the problem? i have absolutely no catalytic converter. somebody please help my MPG's are sucking
Generally with no catalytic you should gain some mpg's (in theory), but the car will smell rich without the cats. Are you running open headers, or connected through the rest of the exhaust? Do you have both pre and post cat o2's connected? Any cel? Something is off (obviously) but it needs to be traced down. How old are the o2 sensors?
Thread Starter
Pole Position
Joined: Apr 2014
Posts: 206
Likes: 4
From: Miami, FL
one upstream is new and one downstream is new. the header itself goes from the exhaust manifold down to the actual exhaust but i am using the stock toyota muflfers. I thought the smell may be that the phlange was lose but its not the case. i do have a CEL on and it says its ALL o2's, should i just replace all four?
What kind of car? I assume a SC400 since no one really tries to get NA power out of the 2J, right? Is everything plugged back in? Any wires get left on the exhaust and melt? I'd reset the ECU by removing the terminals on the battery and let it set. Try doing that and then resetting the codes at AutoZone and test...
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If your having MPG issues, might want to rethink the turbo and larger injectors.
Not trying to be a jerk, but if your prepping for a turbo may as well get associated with lower MPG. Now, the rich fuel smell will NOT go away without having atleast one cat in place, regardless of how long your exhaust is. My LS1 SC has exhaust all the way back to the diff, with no cats and it burns my eyes especially on cold starts (I hate trees, and carbon foot prints are garbage.) So the smell probably isnt an issue.
How many MPG's did you average BEFORE the headers, and whats your average now? How does the car idle? Is it at the correct rpm? Does it surge? How does it accelerate? Are you still driving the same? Did you double check to be sure everything (specifically any vacuum lines) were reinstalled properly?
Not trying to be a jerk, but if your prepping for a turbo may as well get associated with lower MPG. Now, the rich fuel smell will NOT go away without having atleast one cat in place, regardless of how long your exhaust is. My LS1 SC has exhaust all the way back to the diff, with no cats and it burns my eyes especially on cold starts (I hate trees, and carbon foot prints are garbage.) So the smell probably isnt an issue.
How many MPG's did you average BEFORE the headers, and whats your average now? How does the car idle? Is it at the correct rpm? Does it surge? How does it accelerate? Are you still driving the same? Did you double check to be sure everything (specifically any vacuum lines) were reinstalled properly?
If your having MPG issues, might want to rethink the turbo and larger injectors.
Not trying to be a jerk, but if your prepping for a turbo may as well get associated with lower MPG. Now, the rich fuel smell will NOT go away without having atleast one cat in place, regardless of how long your exhaust is. My LS1 SC has exhaust all the way back to the diff, with no cats and it burns my eyes especially on cold starts (I hate trees, and carbon foot prints are garbage.) So the smell probably isnt an issue.
How many MPG's did you average BEFORE the headers, and whats your average now? How does the car idle? Is it at the correct rpm? Does it surge? How does it accelerate? Are you still driving the same? Did you double check to be sure everything (specifically any vacuum lines) were reinstalled properly?
Not trying to be a jerk, but if your prepping for a turbo may as well get associated with lower MPG. Now, the rich fuel smell will NOT go away without having atleast one cat in place, regardless of how long your exhaust is. My LS1 SC has exhaust all the way back to the diff, with no cats and it burns my eyes especially on cold starts (I hate trees, and carbon foot prints are garbage.) So the smell probably isnt an issue.
How many MPG's did you average BEFORE the headers, and whats your average now? How does the car idle? Is it at the correct rpm? Does it surge? How does it accelerate? Are you still driving the same? Did you double check to be sure everything (specifically any vacuum lines) were reinstalled properly?
one upstream is new and one downstream is new. the header itself goes from the exhaust manifold down to the actual exhaust but i am using the stock toyota muflfers. I thought the smell may be that the phlange was lose but its not the case. i do have a CEL on and it says its ALL o2's, should i just replace all four?
Your car is obd2 so you can use an obd scanner to check all the codes. Resetting the ecu will clear old codes, and if you still have issues they should show up as codes. Then go from there
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