Chevy 2010 Aveo5 LT, 1.6l Engine, Auto Transmission, Hatchback.
165,000 Miles
After misfire P0303, replaced coil pack, spark plugs OK, Vehicle reported P0420.
No instance of the code before Misfire, verified by scanner.
Live data from scanner shows:
STFT: Bouncing between -6.0 to 3.0
LTFT: 6.0
o2 sensor 1: showing correctly
o2 sensor 2: cold - bouncing, at full temp (highway speeds) flat voltage between .5-.7 volts
Both Cat convertors changed less then a years ago with OEM.
Brand new o2 sensors replaced at the same time with OEM.
Full exhaust replaced at the time of Cat replacement.
Vehicle shows no power reduction, no acceleration issues, no starting issues.
Noticed recent poor fuel consumption.
Possible resolutions?:
Leaking fuel injector(s), not overly noisy
Bad or fuel soaked EVA canister (no codes shown)
Bad #2 o2 sensor
Manifold Catalytic Converter
Ideas?
Thanks for your help
What makes this problem better or worse?
acts normal
How long has your 2010 Chevrolet Aveo5 had this problem?
RepairPal Certified shops can diagnose and repair your 2010 Chevrolet Aveo5. They provide transparent pricing with a minimum 12-month or 12,000-mile warranty on repairs and services.
Hello, Dave here, contributing to RepairPal and providing expert advice since 2010.
I can understand and respect that you've replaced all these components. Including the catalytic converter in the past. But we don't know if the misfire that you were experiencing was bad enough to run so much fuel through your catalytic converter that it caused another failure.
The easiest way to know what is happening here is to measure the exhaust gas before and after the catalytic converter. If there is no change in the reading, the converter is not doing his job.
You list possible resolutions - but at the end of the day it all comes down to catalyst operation. If you had leaking fuel injectors, this catalyst inefficiency code would come because of damage. There is no canister concern causing us code. Yes, you could have faulty oxygen sensors before or after the catalytic converter, or a wiring or wiring connector issue. Especially if it's not original equipment. However, you have indicated that you have used original equipment parts.
I would clear the code, check for any exhaust leaks at the manifold - or anywhere else, and recheck operation. If the code P0420 comes back, it's likely the catalyst again.
https://repairpal.com/auto-repair-near-me
Click the link or call us at 877-913-1554. We'll gladly find you a certified RepairPal shop in your area.
