Please if someone could help..
I’ve been experiencing some issues with my car and could use some advice. Here’s what’s going on:
Symptoms:
- At idle, the car feels like it’s having small, random hiccups or misfires. They’re not very aggressive, but definitely noticeable.
- Interestingly, when I switch to Sport+ mode, the hiccups seem to reduce or almost kind of go away?
- Under normal throttle and driving conditions, I don’t notice any issues or misfires.
- I haven’t been driving aggressively, just normal commuting since these issues started.
- The problem seems to be gradually getting worse.
Diagnostic codes I pulled: (I don't know what inactive means)
- 12B505 – Heating Lambda Sensor 1 Bank 1, Heater Error
- 190302 – Tank Ventilation and Purge Air System, Fine Leak (Leakage > 0.5mm)
- 21A026 – (Inactive) Combustion Engine: Abnormal Key/MSA Start Detected
- 20E120 – (Inactive) Suspected Leaks in Air-Carrying Components
- 11A030 – (Inactive) Low-Pressure Fuel System, Electric Fuel Pump Adaption Value Out of Range
- 1FBD08 – (Inactive) Ready to Drive: MSA Deactivation Request from BDC
Possible causes I’ve considered:
- I installed a downpipe myself with a friend—there’s a chance something wasn’t connected properly. Could this cause these symptoms?
- I might have over- or under-torqued the spark plugs during a recent service. Could that cause the misfires?
- I removed the intake muffler and replaced it with gaskets. Could this create an intake leak?
- Could the fuel tank breather valve be failing, causing some of these codes?
If anyone has experienced something similar or can point me in the right direction for troubleshooting, I’d really really appreciate it.
Thanks in advance, I'm really worried.
