Downpipe question

vito2279

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My Specs:
Emira I4
Hello, new turbo owner here. Is there a downpipe for the 2.0 that doesn't cause a check engine light? Everything I've found so far says to expect a check engine light if installed. Thanks in advance!...
 
Hello, new turbo owner here. Is there a downpipe for the 2.0 that doesn't cause a check engine light? Everything I've found so far says to expect a check engine light if installed. Thanks in advance!...
Mach5, no CEL or any warning. Mine was installed almost a year ago with close to 4000km, all good. I just switched to a de-cat straight pipe recently so if you dun mind used, I am willing to part with it. @ManualB also has the Mach5 and you can ask him for opinion.

Mach5 downpipe has a layer of special mineral inside to bypass CEL so you dun have to mess with o2 sensor.
 
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i dont think there is a downpipe that has been proven to consistently be CEL free from one car to another. i think its luck and/or hit or miss. the post cat O2 sensor is super sensitive and a little too far, too lean.... a little too close, too rich., both CEL. then its finding a sensor spacer that will try to dial get it right. I have a few spacers to try if i get a CEL....lol. Hopefully with a real ECU tune, that can be dialed out.
 
i dont think there is a downpipe that has been proven to consistently be CEL free from one car to another. i think its luck and/or hit or miss. the post cat O2 sensor is super sensitive and a little too far, too lean.... a little too close, too rich., both CEL. then its finding a sensor spacer that will try to dial get it right. I have a few spacers to try if i get a CEL....lol. Hopefully with a real ECU tune, that can be dialed out.
Thanks so much for the reply. Hopefully a real tune becomes available soon!..
 
i dont think there is a downpipe that has been proven to consistently be CEL free from one car to another. i think its luck and/or hit or miss. the post cat O2 sensor is super sensitive and a little too far, too lean.... a little too close, too rich., both CEL. then its finding a sensor spacer that will try to dial get it right. I have a few spacers to try if i get a CEL....lol. Hopefully with a real ECU tune, that can be dialed out.
My Emira club has more than 10 ppl with the Mach5 installed and none of us ever get CEL because of our exhaust system. I dunno why this is unheard of in the states but this method is quite popular in China for owners who do not want to mess with ECU tuning.
 
My Emira club has more than 10 ppl with the Mach5 installed and none of us ever get CEL because of our exhaust system. I dunno why this is unheard of in the states but this method is quite popular in China for owners who do not want to mess with ECU tuning.
regional emission specs differences??
(then again, has anyone in the US installed a Mach5 DP yet?)
 
Thanks so much for the reply. Hopefully a real tune becomes available soon!..
ECU tune for turbo is available, just not state side yet, should be soon.
 
My Aerie sports cat/downpipe eventually started throwing both lean and rich, sometimes at the same time lol. Tried a spacer and then the sensor was too far away - it's very sensitive. I ignore the CEL for now, will vanish once ECU is tuned. In US we don't use the same number of sensors from the Chinese cats so we plugged one (two? I forget) bungs. Lotus tech here thinks there is different emissions logic in the US cars vs other regions also...

Buy that Mach5 from @675430VME ! be the guinea pig for those who won't go the ECU route and write out codes
 
My Aerie sports cat/downpipe eventually started throwing both lean and rich, sometimes at the same time lol. Tried a spacer and then the sensor was too far away - it's very sensitive. I ignore the CEL for now, will vanish once ECU is tuned. In US we don't use the same number of sensors from the Chinese cats so we plugged one (two? I forget) bungs. Lotus tech here thinks there is different emissions logic in the US cars vs other regions also...

Buy that Mach5 from @675430VME ! be the guinea pig for those who won't go the ECU route and write out codes
@Milk242 brought the Mach5, will see if his hold up. Btw Aerie also CEL in Chinese emission.
 
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Haven’t installed, waiting for the exhaust to come in and also reach 1000 miles lol
 

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