Hey everyone,
I've got a 2015 Fiesta ST with 170k miles for a month and have been enjoying it. However, I’m now facing some issues and need help diagnosing them.
Background & Initial issues
Recent issues
I am guessing at the oxy sensors or the cat clogged. Or exhaust/intake leak, or maybe the evap system finally give up? But I'm not sure.
If anyone has experienced similar issues or can suggest diagnostic steps, I’d really appreciate it! Thanks in advance!
I've got a 2015 Fiesta ST with 170k miles for a month and have been enjoying it. However, I’m now facing some issues and need help diagnosing them.
Background & Initial issues
- The previous owner had an EVAP issue and replaced the purge valve for a temporary fix. He mentioned that ideally the whole EVAP line should be replaced but I haven't done that.
- I’ve been driving for about a month with these codes: P1450 – Unable to bleed up fuel tank vacuum, and P0455, P0456, P0457 – EVAP system leak detected. Everything seemed fine. The only noticeable issue was that after a full gas fill-up, the car would have trouble starting and would need several ignition attempts.
Recent issues
- Last week we had a big snowstorm and so I took it to go drifting in a snow and ice covered parking lot for about 30 minutes. The car was consistently revved to 6000 rpm during then.
- After that, the engine is MUCH LOUDER than before. I can tell it’s not the normal sound. It's like low deep whimpering. Even at 2000-3000 rpm, the noise can annoy the whole street. I posted a video here: View: https://youtu.be/5bElLlma3fE
- The sound may not be from engine alone–when lightly pressing the gas pedal during driving, there's almost no change on the rpm, but the noise can become much louder. After letting off the gas, it became quieter again.
- I checked the codes. Except for the old EVAP ones, now I have a new P219A – Bank 1 Air-Fuel Ratio Imbalance.
- For fuel consumption, I used to get 28 mpg on my usual urban commute. And now I’m getting 19 mpg with the same driving conditions.
- I think there is some power loss but I'm not completely sure on this.
- I checked the oil level it's fine.
I am guessing at the oxy sensors or the cat clogged. Or exhaust/intake leak, or maybe the evap system finally give up? But I'm not sure.
If anyone has experienced similar issues or can suggest diagnostic steps, I’d really appreciate it! Thanks in advance!
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