Been browsing this forum for a couple of years and now have a problem you may be able to help with! Note I am no mechanic so answers as if you're talking to a 3 year old would be appreciated!
I have a 53 plate Astra G 1.6 SXI. The Emissions light came on a couple of weeks ago. I have finally managed to read the error code via Digimoto which gives it as P0400 (Exhaust Gas Recirculation Flow Malfunction). I also had a nosey around which caused me to notice a reading that doesn't look right - 'O2 Voltage' - Bank 1 sensor 3 through bank 2 sensor 4 all give a reading of 0.635, whereas bank 1 sensor 1 reads as 0.65 and bank 1 sensor 2 says 0.755.
I have noticed the odd stutter and sometimes it is difficult to start recently.
Also, I get what sounds like a slight exhaust blow sound, but only when the engine is struggling (eg. Trying to accellerate in too high a gear).
Now, a quick google would suggest to me (As totally ignorant in this area!) a faulty EGR valve or a faulty lambda sensor.
Some expert advice from you guys would be much appreciated!