CPE Downpipe w/ Hi Flow Cat Strong Gas Odor?

staples187

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2007 MazdaSpeed 3
I have the 3" CPE Downpipe with the Hi Flow Cat going to a 3" GHL Exhaust. It seems to be running extremely rich. Everytime I turn the car on I get a strong odor of gas and my mpg has gone down a bit about 3mpg. If I drive around for a while and come to a stop it doesn't seem to be too bad, but if I rev it or run WOT it has a strong odor. I'm not 100% sure but I may also have an issue with fumes getting into the car through the heater. I can only think of a possible leak between the turbo and the downpipe itself, any ideas?

I don't want to be running so rich I blow my cat out.
 
It could be a leak.

By opening up your exhaust channel to 3" all the way, you are going to start smelling the real smell of gasoline. It is something normal.

As for the rich factor, only a tune could fix that.
 
uhh.. a leak in your exhaust wont make your car run rich or reek of fuel. try and find out were the smell is comming from first then see if it only does it when its cold vs hot then let us know. good luck
 
uhh.. a leak in your exhaust wont make your car run rich or reek of fuel. try and find out were the smell is comming from first then see if it only does it when its cold vs hot then let us know. good luck

I've had the downpipe on for 3 months now and it just started doing it (weather has been getting colder, going from the high 60s low 70s to 40s and even below.) I've checked for leaks around where the downpipe and turbo meet and there hasn't been any odd sounds nor has there been strong odors of fuel. It does it when I cold start and when I rev the engine. I could just be running extremely rich, maybe the standback will help with this? I got in touch with CP-E today awaiting their callback. I've never had a downpipe or a turbo car before but I am very familiar with the N/A scene. Maybe the cat is just there for emission purposes and there really isn't any restriction between the offroad and the high flow.
 
u know i do remmebre my wrx doing the same thing when the weather started to change. on a cold morning the car would run super rich and smell like gas somtimes. does the problem go away after you drive it for a bit?
 
u know i do remmebre my wrx doing the same thing when the weather started to change. on a cold morning the car would run super rich and smell like gas somtimes. does the problem go away after you drive it for a bit?

Sure does... If the car warms up and I come to stop and let it idle it's fine. If I rev it though to about 4k it will make it smell. I really think it's just an issue with this car running extremely rich. If I can get ahold of the plug and play for the standback I can change my A/F around.
 
the cp-e cat has a metal core, not ceramic. you shouldn't have to worry about damaging it from what I can tell.
 
the cp-e cat has a metal core, not ceramic. you shouldn't have to worry about damaging it from what I can tell.


Well I talked to someone else with the cpe full turboback with the high flow cat and he hasn't had any problems. So there's two possibilities; 1, The O2 sensor is not seated right, 2, there's a problem with the downpipe to the ghl exhaust because I've heard of that before.
 
If im not misstaken don't turbo vehicles run rich on start up to try to bring the car up to temp quickly cause cat's don't perform properly till there fully heated. Since the turbo is in the way it takes turbo vehicles a little bit longer to get the cat up to temp. Running rich on start up is a way to get temps to shoot up quickly.
 
i've been experiencing the exact same problem... the smell seems to be on and off but its never consistant... there are times i have to drive with the window down in -10 degree celcius because of the smell
 
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