For US I4 owners (may apply elsewhere but I have no idea)
FIrst off, the manual is wrong there are not two additional ports on the stock cat which are labelled DPS (differential pressure sensors) we only have two O2 and two temp sensors. Both the GRP and the Aerie cats have 6 ports so you just have to cap two of them off.
The stock cat is massive...my shop had to remove three engine mounts, move the engine forward a few inches to jenga the cat out through the boot window behind the liner. It won't come down below if you lift the car. Besides that it was very straightforward.
You WILL throw a cat efficiency code and always have a permanent one stored, a pending code...and then after a few clean restarts or around 100 miles it wil confirm the code and you'll get a CEL. Which by itself is not a big deal other than the light being on - it won't force your car into limp mode or anything and makes no adjustments, it's just a warning. I have a BlueDriver OBD2 bluetooth dongle so it just sits in the plug and takes seconds to open my phone and clear it. I've only seen it once published as an active CEL but I can see the permanent and pending codes.
How does it feel and sound?
In combination with the Aerie exhaust the cat is awesome. Deep, throaty sound on throttle, quiet when not. You can leave your exhaust valve on open and just drive around town in touring it won't be loud at all. Mostly there is a very easy to notice increase in throttle response, breathing, and torque...very noticeable. So much so that I don't mind either seeing the CEL or just clearing it every so often when it pops up.
So NO for US cars Aerie is wrong, the car will throw a code...the US based I4 with our emissions may be different on how it's calculating everything than other regions. But it's just a light on the dash, can always tape over it (!)
highly recommend getting either - @docron will install his GRP and see if they got the spacer length just right to not throw a code, the ecu is just reading the differential between the two sensors and at least on mine the delta isn't big enough so it triggers the P0420 - I'll record some video samples soon
Does anyone have a US I4 with the Aerie cat? are you always getting the same code?
FIrst off, the manual is wrong there are not two additional ports on the stock cat which are labelled DPS (differential pressure sensors) we only have two O2 and two temp sensors. Both the GRP and the Aerie cats have 6 ports so you just have to cap two of them off.
The stock cat is massive...my shop had to remove three engine mounts, move the engine forward a few inches to jenga the cat out through the boot window behind the liner. It won't come down below if you lift the car. Besides that it was very straightforward.
You WILL throw a cat efficiency code and always have a permanent one stored, a pending code...and then after a few clean restarts or around 100 miles it wil confirm the code and you'll get a CEL. Which by itself is not a big deal other than the light being on - it won't force your car into limp mode or anything and makes no adjustments, it's just a warning. I have a BlueDriver OBD2 bluetooth dongle so it just sits in the plug and takes seconds to open my phone and clear it. I've only seen it once published as an active CEL but I can see the permanent and pending codes.
How does it feel and sound?
In combination with the Aerie exhaust the cat is awesome. Deep, throaty sound on throttle, quiet when not. You can leave your exhaust valve on open and just drive around town in touring it won't be loud at all. Mostly there is a very easy to notice increase in throttle response, breathing, and torque...very noticeable. So much so that I don't mind either seeing the CEL or just clearing it every so often when it pops up.
So NO for US cars Aerie is wrong, the car will throw a code...the US based I4 with our emissions may be different on how it's calculating everything than other regions. But it's just a light on the dash, can always tape over it (!)
highly recommend getting either - @docron will install his GRP and see if they got the spacer length just right to not throw a code, the ecu is just reading the differential between the two sensors and at least on mine the delta isn't big enough so it triggers the P0420 - I'll record some video samples soon
Does anyone have a US I4 with the Aerie cat? are you always getting the same code?
