Yesterday I bought a used Citroen C4 Grand Picasso 2.0 I 16v VTR+ ESG petrol from a trader. It's an auto 07 plate and has just over 68,600 miles on the clock. Test drive was fine and the 70 mile drive home was also ok.
This morning I went out and the car started fine but driving away it sounded a bit like a a motorbike when I pressed down the accelerator, with the noise stopping when I took my foot away. The car felt a bit jolty changing gears too. Rang the place I bought it from and they asked me to try get a mechanic to have a look at it and let them know what was wrong. I had to nip out this afternoon and the noise was happening again but then the car seemed to get stuck in first and the car bleeped with a 'depollution system fault' and engine management light. After that the car seemed to struggle changing up gears, especially 3 to 4. Felt a bit sluggish.
Managed to get it home and called out AA to have a look at it. I explained what was happening, he had a look under the bonnet and revved the engine a bit. White smoke was coming out the back at this point. He plugged in his fault reader and the following codes came up:
P0170 - fuel correction bank 7
P0300 - random cylinder misfire
P0172 - fuel/air mixture rich
P0130 - o2 sensor, bank 7, sensor 2 out of range
The AA guy said it could just be a faulty o2 sensor but then again it might not be. Most likely the exhaust. I told him to leave everything as is for the time being as I'm going to give the trader a call tomorrow. I've been googling a lot (which can sometimes be a curse!) which throws up a possible hole in the exhaust etc etc. I did originally take a recording of the sound and sent it to a mechanic friend (not local) who says it sounds like this could be the case and they (the garage) could have patched it with putty or something hence there being no sound yesterday. I'm in two minds about what to do. Do I let them have a chance at fixing it or give it back an ask for a refund? I've been stung by a French car before (b*** Renault) and I really don't want to go through the aggro again to be honest. The trader also owns a garage and mot'd the car the day before I bought it with no advisories or anything. I know that under the October 2015 consumer act I do have the right to return the car for a refund within the first 30 days or ask for them to fix it. I think I'd prefer to ask for a refund at this stage, it's something I just don't need right now. The car was £4k and I'd expect better than it to be faulty a day after purchase. AIBU? Any advice would be appreciated!