[Neyborg]

Lately I've been trying to find out why my 435D often shudders at low RPM (between 1krpm-1.5k rpm mostly) cruising.

In trying to narrow the problem down I had the car carbon cleaned yesterday, which includes cleaning out any combustable areas. My hope was that perhaps the EGR full of sh*t and this would eliminate the shuddering issue im experiencing.

Well, the car IS running notably smoother actually, on start up and on general acceleration, however the shuddering issue at low RPM cruising is still there.

Interestingly, one thing that the guy noticed when he plugged in was 2 error codes

283300 - Oxygen Sensor before catalystic converter, heating, activation, Open circuit - Intermittent

282D00 - Lambda Sensor heater before catalyst, activation, short circuit to plus - Permanent

Does anyone know what (if any) egregious driving symptoms you'd notice with the car throwing out these error codes? Could that be causing the juddering im getting? and are they both straight forward fixes?

[Neyborg]

bumping, any input massively appreciated, cheers.

[thejeremyman9]

Did you check the upstream O2 wiring...? I assume the upstream O2 is used for engine control on the D just like the gasoline cars...

[Neyborg]

I'm not technical so haven't checked much no.

Just interested in whether this error could cause the car to stutter at low rpm cruising speeds.

As the quote to replace it is £400... which seems high to replace a sensor. I'm fine paying it if that could be giving me the symptoms im experiencing, but if its something and nothing and largely symptom-less, then I obviously see much less point in having it fixed.

[thejeremyman9]

Originally Posted by Neyborg

I'm not technical so haven't checked much no.

Just interested in whether this error could cause the car to stutter at low rpm cruising speeds.

As the quote to replace it is £400... which seems high to replace a sensor. I'm fine paying it if that could be giving me the symptoms im experiencing, but if its something and nothing and largely symptom-less, then I obviously see much less point in having it fixed.

Well yes, O2 issue can, but of course many other things can as well. The codes are pointing to the O2 but that's no guarantee that's the problem. That does seem high, not sure if that's because you are a diesel or that's just excessive cost. Without data logs or further testing and diagnosis, you probably just need to find a shop you trust.

[Neyborg]

Interesting, thanks for the reply.

Just a little update on this one after further testing.

In an effort to try and investigate/deduct the problem, downloaded the XDelete app and flashed the ECU for the XDrive to run full time RWD. I thought if the problem persisted then I could rule out the transfer box I guess? A lot of people seem to see XDrive causing the symptoms I’m having.

Unfortunately the problem has persisted when the car is running in RWD mode.

Couple other things I’ve noticed is; the car does it much more when I run the car for the first time in each day before it’s fully warmed up. Once the oil temp read out gets to 100 ish it tends to happen much less.

Also it’s not the traction system as I’ve turned that off and it happens just as much then too.

So running out of ideas a bit as the only errors are to do with that oxygen sensor that I mentioned.

Does anyone think it could be anything else drive train wise? Or is this sounding more like an engine / power train issue given the above?

At £120 p/h for investigation at a specialist I’m trying to atleast
Narrow it down a bit.

Maybe it is related to that oxygen sensor?

[thejeremyman9]

O2 sensor or wiring seem the most likely...

[Neyborg]

Originally Posted by thejeremyman9

O2 sensor or wiring seem the most likely...

Another update, could be coincidental but BMW actually contacted me yesterday to let me know there is another recall due for my EGR cooler. Despite already having this done last year.

I asked if it could cause the symptoms i'm seeing, but the lady i spoke to wasn't technical. So i'm gonna get that done and ask them to take a look at the oxygen sensor while they're at it. As I suspect all of this is now related.