[mistabam92]

Hi Everyone, just discovered this thread so thought i'd share my 320i ownership story - mine isn't actually all bad but it's not great, lol

So, I picked one of these up in June 2020 last year as the first car I've owned since moving to London about 5 years ago. Working on an extremely tight budget, I found a Le Mans blue E91 320i M Sport with 6 speed manual, the N46B20 engine and 151k miles, in let's say 'less than ideal condition' and picked myself up a bargain.

The main issue I knew about before buying was the valve stem seals as there was an advisory for blue smoke in it's previous MOT history, so this was the first thing I got fixed after a few test journey's to fully confirm the issue. KMK in Croydon sort this for about £700, not too much bother.

However, I then spent the next few months working out a whole variety of other issues on this car, the most annoying/expensive of these being that the rear differential was failing. It wasn't instantly noticeable for some reason but once the garage who did the valve stem seals pointed it out my god, was the whine on that thing annoying! I tried changing the diff oil but if anything that actually made it worse, really not ideal.

Sounds like the diffs on the 320i do occasionally go bad, but wouldn't say this is a common issue on these cars from my research. Regardless it had to be sorted, so reluctantly got the the diff fully refurbished at KMK for another £700ish.

Those were the 2 major/annoying ones that did cost me a fair whack, but in terms of other mechanical repairs/maintenance I have also done;
-Rear shocks & bump stops
-Rear upper & lower control arms
-Rocker cover gasket (done with valve stem seals)
-Oil filter housing gasket and oil cooler gasket
-VANOS solenoids & O-Rings
-Crankshaft oil seal
-Idler pulley, tensioner pulley & serpentine belt
-Front discs & all 4 brake pads
-Spark plugs

Now, at least part of the above is down to the fact that this was a 150k mile car when I bought it so some of that was pretty understandable and I was prepared for some maintenance, but I could not believe the number oil leaks this thing had/developed, it was absolute madness in the first few months!

Thankfully, the car is actually running pretty sweetly now and I have also now done a couple of mods to it that I would 100% recommend to make the car a bit more fun to drive/look nicer;
-Black kidney grilles
-Wheel spacers - 20mm rear, 12mm front
-K&N Performance air filter with bottom of airbox removed
-Custom Powerflow Cat-back exhaust system with back box
-CDV Delete

SO! Fast forward to today and I have 2 remaining mechanical problems, which are;
-An intermittent P0430 code which pops up after extended motorway driving, I assume this is a result of the oil passing through the exhaust & cats before the valve stem seals were done. I tried Cataclean and have also tried the spark plug anti-fouler trick on the one post-cat 02 sensor I could actually reach but that didn't cure the issue, so I'm going to have to try and reach the other one at some point soon and see if that solves it. Anyone else tried this method?
-The car has a slightly mysterious coolant leak that I haven't really investigated yet, but it is losing a bit of coolant so does need to be resolved. Anyone dealt with any common coolant leaks on the N46/have some advice on where to start?

Hope my story gives some context to owning a high mileage 320i, I'm hoping with the love and money I've thrown at it it keeps me mobile and having fun in it for at least long enough until I can find a rare as f**k manual E91 335i!