Bought a modded Fiesta ST but...

[SteveS]

The P0420 code indicates a problem with catalytic convertor function. This can be the result of a failed catalytic convertor but more commonly from a failed O2 sensor. It is diagnosed by testing the O2 sensors and replacing if bad, and then repolacing the catalytic convertor if there's still a code.

 

[SteveS]

I looked at the Edge website. They do truck modifications. The only part they sell for the Fiesta is an Amp'd pedal "boost" which is used to alter the throttle pedal response. It doesn't actually do anything to the engine.

 

[61CAV]

https://www.summitracing.com/search/brand/edge-products
How about this? Just an idea

 

[SteveS]

No. If the car is tuned it will have a Cobb Accessport. It's the only one for the Fiesta ST. It is also possible that the car has a tune but the Accessport was removed prior to repossession.

 

[61CAV]

The guy that runs the Edge said if someone came to him, they would need this...Cobb Tuning AccessPort V3 Ford Focus ST 2013-2018 | Fiesta ST 2014-2019.
So, that's my next purchase. 👍

 

[Focused]

Secretary of State "S.o.s" in Michigan are responsible for functions that typically associated with the DMV.

https://www.michigan.gov/sos

https://www.edgeproducts.com/?srsltid=AfmBOopN1PZZuy1jvUtSBeYavhOArLdtQSDFDVPJ3oinYBm1MROovAZd

But again, im not a car person. I provided what I can see. Im taking it to a dealership my mom takes her 98 Vette to, so they can put it on a lift, and go over everything.
1. What I have provided about is what I've observed, and the 0420 code, and my boost starts spooling at 2k i believe, and I have a small drone sound in 2nd gear when accelerating, short but noticeable.
2. I dont know who Edge is, but I provided a website.
3. If my car was just a fiesta SE, would you put an ST sticker on it? Point is.. if Edge does tunes, why would you have a sticker for nothing. Auto sale shops put stickers on cars when they sell them.
I wanted ideas, help, have conversations, find out it what some did..what worked, what didn't. Good parts that builds strength and rigidity.

It took a month to get my car, Navy Federal owned it, bc someone stopped paying. I bought it within 2 days of the car arriving to the dealer in Michigan. Thats it. I've had it for a day.

The guy that runs the Edge said if someone came to him, they would need this...Cobb Tuning AccessPort V3 Ford Focus ST 2013-2018 | Fiesta ST 2014-2019.
So, that's my next purchase. 👍

A Cobb AP is not exactly cheap, so unless you just have no care about where your money goes and you enjoy going on potential wild goose hunts, I’d suggest just pausing on any purchases until you know exactly what you’re dealing with, and knowing what the best course of action is to deal with whatever you’re dealing with.

Friendly advice: slow down, listen to everyone’s input here, and just wait til you know what your car has. Everyone’s been super patient here trying to help, but this could quickly turn into a train wreck if you decide to get a bunch of parts without knowing what’s what.

 

[61CAV]

My cars funds are paid monthly by the VA. Im looking to replace old parts that wear down. If an upgraded clutch is better than a stock one, I'd choose a better one, If I get to the point.

 

[dhminer]

The P0420 code could be either failed o2 sensor or the previous owner installed an aftermarket downpipe with high flow cat or catless. Do you have a way to get under the car?

Take some more pics of the engine bay and we’ll help identify stuff. Get the front down by the throttle body (between the engine and the front of the car), up under the cowl at the back of the engine, and from underneath if you can.

Can see in the first pic an Injen CAI and whoosh induction hose. Your crossover pipe looks aftermarket too but can’t tell with certainty from the photos. Here are links to the shit you have already.

https://whooshmotorsports.com/colle...ta-st-1-6l-turbo-4cyl-wrinkle-black-short-ram

https://whooshmotorsports.com/produ...low-silicone-induction-hose-kit-free-shipping

 

[61CAV]

Thank you. So under further review, I got a new oil change. Im not sure what was used, but my next oil change is in 150,000 miles. But regardless im going to get it changed way sooner. Fuel injectors were cleaned, and its all straight pipe. :/ I learned the average oil change shop does Trans fluid change, but not on Fords Fiesta STs. :/ so only ford dealerships, or a certified mechanic.

 

[SteveS]

Your receipt or even the sticker on the windshield should say what oil was used. It should be at minimum semisynthetic like the OEM Motorcraft oil. The weight is 5W-20. The manual suggests a pretty long oil change interval and there is a wrench-shaped light on the dash that will tell you when to change the oil (also on a long interval). But probably almost everyone on this forum changes the oil at 5,000 miles or maybe even 3,000 miles.

Transmission oil needs to be a very specific type so it is a good idea to stick with a Ford dealer for that.

If the car is straight piped that explains your P0420. Personally I would not leave it that way. The catalyst does not hurt performance, and everything is better about having it working. The ECU changes things depending on what the O2 sensors read, and if there's no catalyst it will be getting bad readings all the time. And pollution is a bad idea.

The car sounds like crap without a full exhaust system with resonators and mufflers.

 

[61CAV]

I would be in that range of 3-5k anyways. I had straight pipe on my 350z, and it wasn't bad. But I need something better on the ST forsure. Now, we've established a straight pipe, what is a good exhaust system? Please dont say stock, but if I have to, I will. It will remove my 0420 code atleast. I dont need a cop follow me around again.