Hi guys. S3 8P is slightly jerky when accelerating from stop. No error/fault codes displayed. Scan tool emission tests suggests "O2 sensor heater failed". I understand there is 2 O2 sensors. Which one could be failing and causing these issues? Not very tech inlcined. Adive would be appreciated
Bad O2 Sensor?
- Thread starter kgashane
- Start date
If there's no fault codes, what pointed you to the 02 sensors, there will be a pre & post sensor, without an error it's hard to know which may cause issues.
Could be other things too?
Could be other things too?
Some additional info: I had new coils, new plugs, new fuel pump (in tank), cleaned MAF sensor, new air filter, new fuel filter, cleaned injectors, carbon cleaned the intake valves
It would appear that the problem is the MAF sensor. When i disconnect the MAF sensor, the car runs better; and the problem (jerky when taking off) resurfaces when i reconnect the MAF sensor. The strange thing is that there is no engine light or any thing of that sort. The scan tool does not pick up anything wrong with the MAF sensor either. When i test the MAF sensor on the scan tool under "live data", it shows a flow rate of about 2.8g/sec at idle (just below 1000 rpm), and it responds by showing an increase in air flow when i open throttle.
I will clean the MAF sensor and give an update.
Can the gromets underneath the engine cover lead to a vacuum leak if they are not fitted? I noticed that i can see the air filter through the holes where the gromets are supposed to be fitted and i suspect that air could be leaking from there
