[Roarsman]

All

I'm getting occasional engine check lights and Drive Moderately messages in my 2013 F31 320d. This only happens in town driving, along with a reduction in performance. Long motorway journeys are just fine - the car goes well.

My mechanic's diagnostic shows:
P0237 Stored. Turbocharger boost-press. Sensor A. Signal too small
P0402 Stored. Exhaust -gas re-circulation. Amount excessive
P0237 Sporadic. Turbocharger boost-press. Sensor A. Signal too small

Is this worth a visit to BMW to expect whatever is causing this to be covered by the EGR recall, or are these codes due to wear and tear on the EGR and is just what happens with a 7 year old 320d?

In the UK - unless you have had a recall letter, which for some reason I haven't - you have to pay your BMW dealer £99 for an EGR inspection. Which is refundable if found to be valid- claimed back from BMW UK. (My VIN and Reg show nothing due in the BMW recall on-line database)

I would be grateful for advice before committing please, ie: either to my local man or trying BMW themselves.

Thanks all

R

[nemz]

If you're mechanically minded and have some tools, primarily a long screwdriver, you can pop the plastic cap off your EGR valve in situ and see if it's sticking open (most of the time) or closed (if it's really bad, engine runs fine like this). Clean with brake cleaner and small soft brass brush to remove all carbon deposits on the roller wheel and the slot in the actuating arm it runs in, lubricate with high temp ceramic grease (oil or normal grease will just carbonise and it'll get sticky again).

Run the EGR calibrate service function in Ista once it's clean and moving smoothly and follow the instructions, the car needs to go to sleep once calibrated for the settings to apply. Once you start the car again, look at the EGR mechanism, make sure it's working fine and pop the cap back on.

This may solve your engine light issues, it's an hour labour max in an indy if you don't fancy the job yourself.

Also check the MAP sensor in the inlet manifold, easy to get to and just a single 10mm bolt to remove and a connector, there should be a hole in it which gets blocked if the EGR isn't working properly or it needs a thorough clean over time/mileage. Unblock it with something soft, don't poke anything metal in there. Clean with a bit of brake cleaner and refit. Make sure the hole in the inlet manifold itself isn't totally blocked with carbon also.

[Roarsman]

Thank you Nemz, that's great advice for all here I would hope. But not mechanically minded enough I'm afraid, so my man changed it for me on the drive. 1 hour's labour as you say and no more messages cropping up since.

Not a recall item then, so glad I didn't trouble myself with that and arguing the toss with BMW UK.

R

[nemz]

Welcome squire, these EGR's cause no end of issues for what is a great engine, albeit with numerous caveats. There is usually a knock on effect from EGR issues when there's been primarily town driving which eventually blocks the EGR port in the manifold/throttle body and impacts airflow significantly.

If your guy is decent which it sounds like he is, ask him if he'd be interested in doing a throttle body/manifold clean with drain cleaner (caustic soda) it'd work out at about 4 hours labour in total and can be done on the drive if you have somewhere you can use a jetwash sensibly without blasting the drain cleaner on plants or grass. The solution itself will neutralise quickly and is only corrosive at high concentrations, however, it will biodegrade your plants and grass (even human bodies) if you don't rinse any overspray off quickly beforehand

Materials required

1 kilo of caustic soda
2 tall sided storage containers large enough to submerge your manifold completely
Nitrile gloves (or use a hook and rinse carefully before handling with normal gloves)
Jetwash (Karcher etc)
Somewhere to jetwash
Eye protection against splashes


1) Add enough hot water to submerge your parts in one container, add plain warm water to the other for rinsing purposes
2) Slowly add approx 500g of caustic soda to the hot water container and mix slowly with a long stick to avoid splashes
3) Remove air pressure sensor from the manifold and the metal EGR fitting from throttle body and keep the o-ring safe
4) Submerge the inlet manifold, throttle body and metal EGR part into the cleaning solution
5) Wait 30 minutes then carefully remove and jetwash
6) Repeat steps (4 & 5) until the manifold, throttle body and EGR fitting looks sparkling
7) Rinse parts in the other container of warm water, add some soap or degreaser to remove any remnents of caustic soda or oil
8) Admire your brand new looking parts that look like they just came out of the factory (almost)

If they were really bad like the ones I usually work on there will be tangible improvements in idle smoothness, power delivery and economy. Chemical cleaning is far better than solvent cleaning (brake cleaner, petrol etc) these create a right stink, mess and hours of scrubbing to get nowhere near the same results

Here's some before and after pictures, first 2 pics are the throttle body fitted to your car (manifold was in a similar state)







https://f30.bimmerpost.com/forums/at...1&d=1617780765

[n00bkiller944]

^^^ WOW! How many miles or KM's were on that?

[nemz]

102k miles on the N47 (first couple of pics) and the other pics are from an N57 that had done 134k

Some pics have duplicated, dunno why

[F30_320D_UK]

Originally Posted by nemz

102k miles on the N47 (first couple of pics) and the other pics are from an N57 that had done 134k

Some pics have duplicated, dunno why

What a difference! Definitely going to do this on my 74k mile 320d soon

[n00bkiller944]

Originally Posted by nemz

102k miles on the N47 (first couple of pics) and the other pics are from an N57 that had done 134k

Some pics have duplicated, dunno why

Wish you were local. I almost want to pull my N47 apart just to check.

[Enabled]

It depends a lot on driving style too.

Babying it will have the intake tract a lot dirtier. (think old VW TDI, ALH engines etc.)

My 110k mile intake was 90+% cleaner than that.

[nemz]

Originally Posted by n00bkiller944

Wish you were local. I almost want to pull my N47 apart just to check.

If you remove the intake boost pipe (single clip) and the 3 e-torx bolts on the throttle body you'll be able get it out of the way whilst still connected to it's wiring to get some pictures inside the manifold with a phone camera.

The easiest way to see if it probably needs a clean is to remove the pressure sensor on the top of the inlet manifold (single 10mm or T30 torx bolt) see if the hole is blocked in the sensor itself and check the port in the manifold where it fits, if blocked, needs a clean.

Originally Posted by Enabled

It depends a lot on driving style too.

Babying it will have the intake tract a lot dirtier. (think old VW TDI, ALH engines etc.)

My 110k mile intake was 90+% cleaner than that.

^^^ absolutely correct, stop start town driving only or faulty EGR valve and it's gonna need cleaning at 70k

[Primax]

I have this errors:

255C00 - intermitent
255B00 - permanent
240400 - intermitent

And small jerks at low rpm.

Should i clean or change for a new one?

[todualex]

WOW any diy available?

[andreigbs]

Originally Posted by Primax

I have this errors:

255C00 - intermitent
255B00 - permanent
240400 - intermitent

And small jerks at low rpm.

Should i clean or change for a new one?

I cleaned the EGR valve when I got these codes, about a month ago now. So far it's been working great. At some point, a new EGR valve may be required.

I'd be interested in an intake cleaning as described here. I did it once upon a time on an old TDI with 197K miles. To my surprise, it wasn't half as bad as some I had seen.

[Primax]

Originally Posted by andreigbs

I cleaned the EGR valve when I got these codes, about a month ago now. So far it's been working great. At some point, a new EGR valve may be required.

I'd be interested in an intake cleaning as described here. I did it once upon a time on an old TDI with 197K miles. To my surprise, it wasn't half as bad as some I had seen.

I've cleaned it, slight improvement. But then ordered a new EGR valve, and its sorted.

Thank you, i think if there is any problem whatsoever, doesn't worth the time and trouble to clean it, better change it already.

[F30_320D_UK]

Originally Posted by Primax

I've cleaned it, slight improvement. But then ordered a new EGR valve, and its sorted.

Thank you, i think if there is any problem whatsoever, doesn't worth the time and trouble to clean it, better change it already.

Is it a simple enough DIY and what was the cost if you don't mind?
Cheers

[Primax]

Originally Posted by F30_320D_UK

Is it a simple enough DIY and what was the cost if you don't mind?
Cheers

My EGR is from Pierburg, found an amazing deal on ebay original Pierburg EGR with bmw packing, brand new for 86€ with shipping:

https://www.ebay.co.uk/itm/184230232362

[F30_320D_UK]

Originally Posted by Primax

My EGR is from Pierburg, found an amazing deal on ebay original Pierburg EGR with bmw packing, brand new for 86€ with shipping:

https://www.ebay.co.uk/itm/184230232362

Thank you sir