N53 fuel injectors (again...)

[meddler]

Thought it was time to return to every N53 owner's least favourite subject...

I got a CEL yesterday on my E91 325i (N53B30 engine) and it was pretty obvious why, given the extremely rough idle and rough running throughout a 10-minute journey. When I stopped I checked the codes and Bimmerlink showed a cylinder 5 misfire (29D1).

FWIW, I'd been tracking misfires for a few months and cylinder 5 was showing as problematic (see this thread: https://www.pistonheads.com/gassing/topic.asp?h=0&...

Cleared the codes and started it up again about an hour later. There was no CEL and no rough running whatsoever - completely smooth, lol.

I'm going to do some investigation by checking plugs for fuel, swapping coil packs, etc. But given the car has 72k miles on the clock and still has the original injectors, I'm going to assume the worst case scenario that it's an injector issue.

Which brings me to the point: Has anyone had any luck recently with sourcing index 11 injectors for the N53? Cheapest I'm seeing new is £430 inc. VAT, which makes me want to set the car on fire and push it off a cliff

[preacherman]

Having replaced all 6 earlier this year @ £390 a pop, I feel your pain!

I stumbled across this thread the other day that points to somewhere selling for £288. I don't know of the retailer so can't comment on how legit they are.

ETA, Link in post is broken but they still seem to be available: https://www.pfjones.co.uk/bmw-3-series-3.0-2005-on...

Edited by preacherman on Friday 18th October 20:37

[meddler]

Many thanks @preacherman. I’ll investigate. £288 is still steep but a pinch compared with £400+!

The other (Ebay) seller on that post is Merlin Diesel, which I believe has stocked legit OE N53 injectors in the past, per this forum and others

[meddler]

So I did a little investigating because I had suspicions about the injectors listed here…

https://www.ebay.co.uk/itm/145912292828

…and here…

https://www.pfjones.co.uk/bmw-3-series-3.0-2005-on...

…because as you can see, the original markings appear to have been taped over. The injectors themselves also just kinda look like they’re not brand new, even though they’re being sold as such.

In both cases, the manufacturer is stated to be Vitesco Technologies, which is (apparently) a company that has its roots in the fuel injector division of VDO, the OE supplier to BMW. But obviously, it’s not clear if these injectors actually came from Vitesco.

Then I came across this on Bimmerprofs…

https://bimmerprofs.com/more-injector-restorers/

…and started reading more on Bimmerprofs about N53/N43 injectors generally.

Bimmerprofs’ central conclusions are (1) that the market is flooded with refurbished injectors being sold as new by OEMs; (2) that the market is flooded with Chinese fakes that are fairly easy to spot; and (3) that there’s no such thing as a “new” N53/N43 injector any more because what you actually get, even when buying “new”, and even from a dealer, is an industrially refurbished injector.

Sorry if all this is known to everyone here, it wasn’t to me. I have absolutely no idea what to do now…

[bmwmike]

You are right to be sceptical.

As far as i'm aware Siemens are the only manufacturer for those injectors, unless the recent supply shortages saw them outsource to Vitesco.

[meddler]

bmwmike said:

You are right to be sceptical.

As far as i'm aware Siemens are the only manufacturer for those injectors, unless the recent supply shortages saw them outsource to Vitesco.

The theory (at least, according to Bimmerprofs) is that *nobody* has made new N53/N43 injectors for several years now, and that all N53/N43 injectors sold as new by reputable dealers since about 2021 - even those coming from BMW - are old units that have been industrially refurbished.

I would love somebody in the know to tell me I'm wrong because that sounds a bit mad to me...then again, Dieselgate...

[bmwmike]

meddler said:

The theory (at least, according to Bimmerprofs) is that *nobody* has made new N53/N43 injectors for several years now, and that all N53/N43 injectors sold as new by reputable dealers since about 2021 - even those coming from BMW - are old units that have been industrially refurbished.

I would love somebody in the know to tell me I'm wrong because that sounds a bit mad to me...then again, Dieselgate...

Haven't heard that one, but haven't had a n53 for about 2 years now so am out of touch tbh, and must admit the reason I sold was the sudden shortage made me realise that those injectors are unique to that line of engines (n43, n53, n54, early n63) and if they became unavailable, those cars will be screwed.

[BOR]

meddler said:

The theory (at least, according to Bimmerprofs) is that *nobody* has made new N53/N43 injectors for several years now, and that all N53/N43 injectors sold as new by reputable dealers since about 2021 - even those coming from BMW - are old units that have been industrially refurbished.

I would love somebody in the know to tell me I'm wrong because that sounds a bit mad to me...then again, Dieselgate...

I know nothing about fuel injectors, but it is common to refurbish certain parts on an exchange basis, and, in itself, is nothing to be alarmed about.

Generally, Design & Development will be asked to advise on the refurb process and formally sign it off, so won't release parts that are known to be sub-standard.

It could simply mean that the metal housings are no longer being produced, so the used ones are stripped and fitted with new internals - for example.

Buying outside the dealer network is obviously different and no guaranties with that.

[bmwmike]

The piezo injectors cannot be refurbished, or at least, they never could. Perhaps they can now - necessity and inventions etc.

[E92_325]

Might be worth calling some BMW specialists and see if they can source something for you. These engines are 10+ years old and injector issues are common across N43, N53 and N54 engines. I imagine there must be a specialist who knows a good source for injectors, be it new or reconditioned. If they can provide reconditioned injectors, you should atleast have a warranty period with it.

[meddler]

BOR said:

I know nothing about fuel injectors, but it is common to refurbish certain parts on an exchange basis, and, in itself, is nothing to be alarmed about.

Generally, Design & Development will be asked to advise on the refurb process and formally sign it off, so won't release parts that are known to be sub-standard.

It could simply mean that the metal housings are no longer being produced, so the used ones are stripped and fitted with new internals - for example.

Buying outside the dealer network is obviously different and no guaranties with that.

Thanks.

So maybe it’s possible that Vitesco are legitimately refurbishing these injectors to “new” standard and adding their own logo to the finished product, to be sold outside the BMW dealer network? And perhaps they’re also refurbishing injectors for BMW to supply BMW-stamped injectors to the dealer network?

Or not.

Anyone?!

[meddler]

E92_325 said:

Might be worth calling some BMW specialists and see if they can source something for you. These engines are 10+ years old and injector issues are common across N43, N53 and N54 engines. I imagine there must be a specialist who knows a good source for injectors, be it new or reconditioned. If they can provide reconditioned injectors, you should atleast have a warranty period with it.

I may well do a ring around to see if I can get to the bottom of it.

[preacherman]

My understanding, purely based on internet research, was that VDO (now Vitesco) were the ones doing the refurbing along the lines of what @BOR suggested; gut the body and replace the internals. Or maybe just the problematic filters inside.

Bimmerprofs were sceptical about the reliability of these "professionally" refurbed units but there are no other options and I quite like my car! I've done 4-5k miles on mine and no problems so far (lots of crossed digits).

I suspect VDO realised that they could milk this cash cow a bit longer so span out a dedicated business arm for it.

[meddler]

preacherman said:

My understanding, purely based on internet research, was that VDO (now Vitesco) were the ones doing the refurbing along the lines of what @BOR suggested; gut the body and replace the internals. Or maybe just the problematic filters inside.

Bimmerprofs were sceptical about the reliability of these "professionally" refurbed units but there are no other options and I quite like my car! I've done 4-5k miles on mine and no problems so far (lots of crossed digits).

I suspect VDO realised that they could milk this cash cow a bit longer so span out a dedicated business arm for it.

Out of interest, where did you buy yours from, and how were they packaged/stamped/stickered?

[KadettE]

I took a punt on a couple of N54 injectors from PF Jones today. Once I get them I can post a picture to show what condition they're in.

[KadettE]

Got the injectors today and they come in sealed boxes as shown on the PF Jones website. Inside the injectors are just wrapped in bubble wrap and not in a plastic case like some ebay pictures show. One of the boxes arrived with broken seal but contents looked identical.

The injectors have the metal caps over the nozzle and to me look like they're indeed from Vitesco. As you can see on the picture there has been some sort of rebadging going on. Don't know if that is old parts being rebadged for resale or what but I'm hoping if Vitesco puts their name on it it'll be a bit closer to OEM spec than the cheap Aliexpress/Ebay stuff. Apparently they spun up some aftermarket division last year focusing on spare parts.

Edit: Apparently my account is too new to post pictures. If there's PMs on here anyone interested feel free to message me for the pic.

[The Conflated Outlier]

Piezo injectors are pretty dreadful but they don't all go wrong. Given the ever dropping value of these cars, I'd recommend that you buy some used ones and code them in yourself. They're easy to fit - slacken the pipe unions, undo a single 11 mm bolt for the retaining plate (one plate holds in two injectors) and wriggle them out. Very careful use of mole grips gets the buggers out if they are reluctant. BMW say you cannot reuse the steel fuel pipe. I say 'bks'. Nip up the unions, slacken them and retighten. I've never had one leak.

Coding them in with a ripped off copy of BMW diagnostics isn't hard - you're just entering the six digit code on the LH side of the injector.

A useable injector is 80 quid or so - just stock up on these and fire one in as and when. Yes, Index 11's are the last revision but they still fail. I've had Index 3's that still work fine.

[RECr]

Do you bother with the replacement seals/clips when using used injectors? I'm sure I've heard the fuel unions are good for 10-15 uses, but also heard elsewhere they're one time use.

[preacherman]

meddler said:

Out of interest, where did you buy yours from, and how were they packaged/stamped/stickered?

I did it through my indy so didn't see the packaging. They sourced them from BMW £40 cheaper than I could find at the time as I think the garages get extra discounts.

I have kept 4 of the old ones that were all on their way out to one extent or another, just in case there ever is a way to refurb them via 3rd parties.

[meddler]

meddler said:

I'm going to do some investigation by checking plugs for fuel, swapping coil packs, etc. But given the car has 72k miles on the clock and still has the original injectors, I'm going to assume the worst case scenario that it's an injector issue.

Thought this might be of interest to anybody following this thread. With the obvious caveat that this is all specific to my car (which is an E91 325i, 2011, 72k miles). It’s maybe a lesson not to jump to conclusions about injector failure.

I realise this isn’t massively scientific, but as mentioned, I’ve been monitoring cumulative misfires (“Number of misfires over life”) over the last six months using Bimmerlink. I’ve seen a sharp increase for cylinder 5 and moderate increases for cylinders 2 and 4. I got a CEL and misfire code for cylinder 5 a couple of weeks ago (disappeared after code clear and restart). More broadly, cold start has been a bit ugly (if not terrible) and warm idle has been getting lumpier.

I finally got the chance to get under the bonnet today. Given that I have limited free time for tinkering at the moment, I decided I'd just get on with it and replace all six coil packs and all six spark plugs, before thinking about possible injector problems.

First up, I logged the latest misfire numbers, then drove the car for 10 minutes, switched it off, and logged the misfire numbers again. Same story: cylinder 5 pulled further ahead; cylinders 2 and 4 also increased.

After letting it cool down, I pulled the coil packs. They appeared to be the factory originals. They were the Delphi ones and the metal casings were a little rusted in places. I replaced these with the Bosch ones that don't have exposed metal parts.

The spark plug wells were in decent order but there was a little bit of oil in two of them - possibly from the previously leaky rocker cover gasket (since fixed). This tips of the coil packs from these wells were a little oily inside and out, as were the lower parts of the spark plug insulators they covered.

I cleaned the oil out of the two wells as best I could with a clean lint-free rag and a long, thin flathead screwdriver, pulled the plugs, and very carefully removed the rest of the oil residue. All six plugs looked in decent shape and none smelled of petrol.

I put the new plugs and coil packs in and fired it up. The start was sweet and so was the idle. Then I drove it for about an hour, giving it some revs during the last half an hour. Then I switched it off and logged the latest misfire numbers.

The result: no additional misfires on any cylinder. Zero. Zilch. And it’s abundantly clear from driving it that the engine is now running as smooth as silk.

(Fwiw, my injectors are Index 9 and the date stamps suggest they were fitted in the factory.)