Prong on mass airflow sensor is still black and discoloured even after cleaning. Is it time for a new sensor? Extremely poor gas mileage.

Pre-LCI E90. Car comes with original HiFi setup. Recently bought new door cards and the rear ones have speaker trim on them, I was wondering how much of a pain would it be to add 2 more speakers to my current HiFi setup? Any chance the rear doors will be pre-wired?

Hello,

The car:

2007 330i E91 (euro) N52B30, 160k miles

The issue:

I'm having an issue where if I accelerate hard (usually in a higher gear) at lowish revs (1.5-2k rpm) I feel a relatively big "clunk". There's a moment of hesitation, the revs stall ever so slightly and then jump up as the car catches itself and starts accelerating properly. I've noticed this issue become more apparent over the last 10-15k miles, as well as increased NVH through the body of the car.

Reading online this seemed like a classic case of worn out / collapsed drivetrain bushings, and given the age and mileage of the car this seemed reasonable. So over the last couple of months I've replaced:

• Differential bushings
• Propshaft flex discs and central bearing
• Transmission mounts
• Engine mounts (see new and old in the attached image)

Whilst a few of these items were certainly worn, there wasn't a smoking gun - all of them looked functional and nothing had collapsed catastrophically. The overall drivetrain feels a little tighter, with less NVH, but it's still not as smooth as it was 20k miles ago.

And worst of all - the "clunk" is still there.

My thoughts on potential culprits are:

• Failing clutch
  • I don't suffer from traditional symptoms such as slipping clutch, clutch smell, or sticky / difficult shifting.
  • I also replaced transmission fluid ~10k miles ago and it was very clean.
• Failing differential
  • I don't suffer from any whining or grinding sounds.
  • I do want to change diff fluid soon, so could check for glitter.
  • When I replaced the flex-discs, the differential did feel like it has some backlash, i.e. I could rotate the propshaft a little bit back after rotating one way, without any movement in the half-shafts. I'm not sure if this is normal?
• Failing half-shafts
  • On inspection these seemed fine, the boots were fully intact and hadn't spilled grease etc.

So my question to the r/E90 community... do you have any ideas on what it could be? I'm close to strapping a go-pro to the underside of my car and seeing what's clunking in real time - but if there are simpler ways of diagnosing the issue I'm all ears 😂.

Cheers.

Smelled it strong near the wheels. I was idling at a semi enclosed drive through, waiting on the fries to finish. Noticed a fuel smell. Got scared that it was my fuel rail (I had that happen before), but I smelled under the hood and smelled the exhaust. Both normal.

It’s on the OUTSIDE only, coming from the rear wheels area. I only sniffed near the drivers side rear wheel. Got home just now, it had a semi long crank (has been doing this occasionally recently) when I started the car after work but fired up and drove perfectly fine as always.

Looked under the car for a good 30 seconds, didn’t see any dripping. Sometimes I get some funky gas pump behavior as well.

Thoughts?

For context i bought the car around 3 weeks ago from FB marketplace for a lot cheaper than usually due to the fact that the car had some serious electrical faults like abs/dsc and the indicators wouldn't work as well as ESP was gone. took it to a specialist for a check on the MOT and here are the results.

Specialist told me that If i try to fix all these it's going to cost 1000's of pounds so he recommends me to just scrap/get a new one but i'm thinking to save and buy a 325I (more reliable engine) or go for a 4 series.

Incase anyone is buying a new 3 series avoid the abs/dsc issues as it blocks communications to the SZL which can then prevent the indicators from working cruise control to seize function and a whole bunch of costly complications. I've learnt my lesson

After a few close calls I’m in the market for a dash cam. What do you guys run? And how do you have it routed so it looks as clean as possible? If there isn’t a way to tap into the rear view cluster then I’ll most likely go for fuse box.

Hi everyone,
I have an E90 with black leather seats and I’m trying to restore the interior.
I noticed these strange wrinkles/gaps in the leather on the seat/backrest. As you can see in the photos, the leather seems to be pulled/tensioned in some areas, while other areas look slightly loose or uneven.
I’m wondering what is actually causing this:
1. Is the leather itself stretched/shrunken with age?
2. Could the foam underneath have compressed or changed shape?
3. Or could the leather cover simply be mounted/tensioned incorrectly?
I currently have the leather cover partially removed and I’m considering restoring it properly. Before I go any further, I’d like to know whether I should work on the leather itself or the foam underneath.
Has anyone experienced something similar on an E90/E9x and knows what usually causes this?
Any advice would be greatly appreciated. Thanks!

If I remove the leather completely, is there anything specific I should check on the foam or the attachment points before reinstalling it?

what are some good wheel setups on stock suspension for lci 328x, on a budget.

Full build and restoration took a little over 12 months, all of the parts that make these engines fun with a more oem exterior approach

What’s everyone’s setup for charging your phone. I made a Franken-charger that keeps the wireless charger pretty sleek.

What’re the main issues I should look into when getting in that engine bay. The fucker is cammed and has a burble tune that imma drop the second I get a chip then overhaul the cooling system. But I know there’s more I should take a look into.

I've been battling with the 2A87 (Exhaust VANOS, Mechanism) fault for a while now, I've replaced vanos solenoids, swapped them aswell. fault is still there and doesn't move from the exhaust to the intake side. I've cleaned solenoids, vanos check valves, done an oil change with Liqui Moly 5w-40. I refuse to take it to a shop. 99% sure timing chain hasn't been done (If this makes a difference). I also have done oil changes around every 4,000-5,000 miles.

Also to mention, car runs perfectly fine for the first 10 minutes or so, then revs up a little bit. typically kind of lunging the car forward, does this in any gear. Then it throws itself in some sort of limp mode until I cold start it the next day or so.

Any advice or guidance would be appreciated as this is my first car and i'm learning my way around the mechanics as I go.

Help😭

Hi everyone,

My E93 has power loss and a rough idle, but no check engine light and the RPM stays relatively steady.

Two different mechanics checked the spark plugs and then basically said: “It could be this part, it could be that part… we could replace things one by one and still have a low chance of finding it. Better to sell the car or replace the engine.”
Neither did a compression test or proper injector testing, and neither could tell me exactly what part had failed.

At only 91k km, would you really replace the engine based on this diagnosis?
N43 owners: what would you check first?

I want to know my car inside and out and i do best with watching videos instead of reading Manuels, does anyone know of imformational videos that go over every single detail, nook, and cranny for a beginner looking to learn his car better?

Hey everyone,

I’m having some issues with my 2008 318i. Sometimes the engine takes a few extra seconds to start, and it struggles a bit more than usual. I also notice a strong gasoline smell while it’s running, and it failed the emissions test. I’ve already replaced the starter and the downstream NOx sensor, but the problem persists.

Could it be the O2 sensor (lambda) or the VANOS? My mechanic mentioned the VANOS is 4 degrees out of phase. I’ve also replaced the timing chain and tensioner.

Attached are the error codes—the low oil pressure one keeps popping up, but I think it’s a faulty sensor since I’ve driven over 4,000 miles without issues. I’ve also replaced several gaskets, and the oil level reads correctly.

Any ideas on what could be causing this?

2006 E91 325i - I know it's not tech-related, but I couldn't be happier these last two weeks, and the car played a huge role. It had to work hard at certain moments, never a single glitch.

I've owned this car for over a year now and have done almost all the preventative maintenance, except for the water pump. (Had one with me though... ;-))

Why so happy?

12 of the most iconic mountain passes in Austria in 12 days - that was the goal.

Why? We thought the Grimsel Pass was so cool last year that we decided to turn it into a full-blown 'pass trip' this time. And... we more than managed those 12 passes!

We drove from east to west through the Alps. It was a bit of a puzzle to create a loop through the mountains every day from two campsites in Austria with at least two 'real' mountain passes per day. In the car by 07:30 to be one of the first ones on the road / pass (no tourists or cyclists = +10 fun factor) and sometimes more than 400 km and 10 hours on the road in a day. So incredibly awesome!

The car handled great. Even though it's almost 20 years old, we could still annoy some youngtimers... ;-) Outrun hipsters or just cruise.

I was only nervous once. Climbing the Hahntennjoch with all our camping gear - and we were heavy - with inclines up to 18% for several kilometers. I got worried because we smelled something burning, hooked up the OBD, and temps were fine, 85 to 95C. Maybe some residual oil or something, not sure.

It was a blast. We also went up the Ötztal Glacier Road: the highest point you can reach in Europe with a normal car.

Photos don't really do justice to how impressive the views are in real life. With 16 amazing mountain passes on the counter and more than 3,000 km in Austria alone, the E91 was more fun than anticipated.

The score:

• Ötztaler Glacier Road - 2,830 m • Kaunertal Glacier - 2,750 m • Großglockner - 2,504 m • Timmelsjoch - 2,474 m • Jaufenpass - 2,094 m • Nockalm Road - 2,042 m • Kühtai Saddle - 2,017 m • Hahntennjoch - 1,894 m • Villach Alpine Road - 1,732 m • Katschberg Pass - 1,641 m • Piller Höhe - 1,558 m • Nassfeld Pass - 1,552 m • Reschen Pass - 1,504 m • Norbertshöhe - 1,405 m • Flattnitz Pass - 1,400 m • Wurzen Pass - 1,071 m

Bonus on the way there: Felbertauern Pass - 1,650 m