If the exhaust has a name like 'Hi-Power' it is either going to be consrtucted lighter than OEM, and/or have better flow for similar weight. Either option is going to have shortcomings with the dB readout at certain frequencies
A couple of years ago neighbours complained via social media when...
Change the oil and filter(s) first. What is the current mileage ?
Apart from a lazy battery, almost all faults I have cleared are down to something mechanical on its way out.
Just by chance I popped into the local Tesco just now and they have Redex DPF cleaner on sale for £3 (250ml).
It might be worth trying a bottle in a near empty tank before taking things apart (or use it directly on the turbo parts if you do start stripping)
Are you doing short trips more than...
Glowplugs are for starting in cold weather and will not make a difference.
Have you listened for any new noises under the bonnet ?
240,000 miles ? the engine has only just run in.
Whilst I've not done it ,on mine, I would consider scraping/vacuuming carbon deposits from around the...
Excellent writeup, a subject that continues to perplex on why cars have continued to be subject to ever increasing emission controls (all good of course) but the ever increasing need to reach out to others online in the first instance (those servers do suck up resources), or drive to an approved...
I would turn it off and leave the car outside in hot weather with all orifices open (boot/bonnet/doors) to let the moisture evaporate as much as possible
There was a claim of old still water stored in cars (often the container for windcreen washer fluid, a plastic pouch like a hospital drip)...
What tools do you have ?
A full sized spare wheel shoved under the front sill would be paramount.
Central London ?
Daylight so you don't end up getting stabbed.
I would go for a replacement TPS from personal experience.
Engine light goes out after three switch off/restarts (or immediately if you have the OBD2 thingy wired up)
Brake calipers, check the disc/pads are not overheating (rear left especially)
Earthing points and corrosion under the bonnet. Don't park/live near the coast.
If a saloon make sure you have a way of getting into the boot.
Get a spare key and always keep a replacement battery for it in the car...