Discussion
A quick question for those knowledgeable in the N53.
Currently got a 325i with the N53, it misfires on a cold start, but after running it for a minute or two, switching it off, waiting for the car to go into sleep mode and then restarting it, it runs nice and smooth(well, as nice and smooth that the N53 can be, wish they just continued using the N52).
Misfire is on cylinder 4(29D0 fault code) and after looking at the injectors, they are all still the original Index 9’s, so my money is on a failing injector and got a new one on order. However, I’m also pulling a 2AAF fuel pump fault code, I’m assuming this is likely unrelated, but wanted to ask if anyone has experienced a fuel pump issue that results in a single cylinder misfire?
Currently got a 325i with the N53, it misfires on a cold start, but after running it for a minute or two, switching it off, waiting for the car to go into sleep mode and then restarting it, it runs nice and smooth(well, as nice and smooth that the N53 can be, wish they just continued using the N52).
Misfire is on cylinder 4(29D0 fault code) and after looking at the injectors, they are all still the original Index 9’s, so my money is on a failing injector and got a new one on order. However, I’m also pulling a 2AAF fuel pump fault code, I’m assuming this is likely unrelated, but wanted to ask if anyone has experienced a fuel pump issue that results in a single cylinder misfire?
Think the 2AAF code is a common one and usually triggered by something else (a wonky injector maybe). I wouldn’t be too alarmed yet - if you fix misfire and it still materialises then start troubleshooting the fuel system.
On a related note, interested in your injector order, are these being produced again or are you just on the long waiting list with everyone else?
On a related note, interested in your injector order, are these being produced again or are you just on the long waiting list with everyone else?
From a historical Bimmerprof (not affiliated, but highly recommended for these engines) remote diagnosis of my N53 630i:
"The reason for 2AAF could be - clogged fuel filter; problems with air-tightness of return pipe, pressure sensor"
It relates to the Low Fuel Pressure parameters.
If these are wrong or erratic it affects the stable delivery of High Pressure Fuel to the injectors.
In my case a replacement LP fuel Filter (under rear seat, passenger side DIY'ble with care) cured the 2AAF code for good.
"The reason for 2AAF could be - clogged fuel filter; problems with air-tightness of return pipe, pressure sensor"
It relates to the Low Fuel Pressure parameters.
If these are wrong or erratic it affects the stable delivery of High Pressure Fuel to the injectors.
In my case a replacement LP fuel Filter (under rear seat, passenger side DIY'ble with care) cured the 2AAF code for good.
Looks like I might be joining the dud injector crew on my 335i (N54).
It struggles to start if left for a few days and it’s chucked up a misfire on cylinder six. It’s in for a service tomorrow and investigation into why it sometimes goes into limp mode on long trips, so I’ll ask BMW to check the injectors as well.
It struggles to start if left for a few days and it’s chucked up a misfire on cylinder six. It’s in for a service tomorrow and investigation into why it sometimes goes into limp mode on long trips, so I’ll ask BMW to check the injectors as well.
I used to own a 2009 530i E61 with a N53 engine which I bought at approximately 39K miles at 5 years old from a main dealer. It had the rough running on cold start up from about a month into ownership. I should have rejected the car then but I didn't. Over the next 3 years it had three sets of coil packs, two full sets of injectors, HPFP, LPFP, NOX sensors, new full exhaust, Cam carriers and numerous other parts I cannot now recall (thankfully all under AUC and then extended warranty) The car would run okay for about a month and then either go into limp mode or shake one day and not the next, worst in cold weather. Added to that it returned a long term average of about 26MPG, drank oil and for a 6 cylinder petrol sounded crap. I traded the car at about 60K miles when the engine light on became an almost daily occurrence. My experience is perhaps one of the worst but the N53 engine should be avoided at all costs IMHO.
g3org3y said:
What's the state of play with the N52 injectors, still v difficult to get hold of?
N53 injectors? They are easier to get hold of but have gone incredibly expensive at over £300 a pop each. I got a whiff that my 2012 may need a new set so i got rid; i'd had it 7 years so fancied a change too, but I knew the car well enough that there was a hint of trouble brewing. That said, apart from a set of injectors in 2015 (under warranty) and a Nox sensor it was a delight to own over the 7 years.bmwmike said:
g3org3y said:
What's the state of play with the N52 injectors, still v difficult to get hold of?
N53 injectors? They are easier to get hold of but have gone incredibly expensive at over £300 a pop each. I got a whiff that my 2012 may need a new set so i got rid; i'd had it 7 years so fancied a change too, but I knew the car well enough that there was a hint of trouble brewing. That said, apart from a set of injectors in 2015 (under warranty) and a Nox sensor it was a delight to own over the 7 years.I’m praying that mine s
t themselves whilst the car is under warranty to be honest. Found a specialist locally who reckon they can fit and code a set of index 12’a for £2,700 which is a big chunk of the asking price of my car. Maybe the M3 wasn’t such a bad idea!helix402 said:
Swop coil from injector 4 to another cylinder to see if misfire follows. A lot cheaper than an injector.
This is going to make me look stupid, but I'll share it to avoid anyone else falling into the same trap.I have an N53 engine. My car was throwing a misfire on cylinder 4 error (I'd already done all the injectors and plugs). Common advice is to swap the ignition coil to another cylinder, and see if the fault moves with it.
So I did move it, and the fault moves with it (checked with inpa)
New coils ordered and installed - next day shaking, cel, and misfire on several cylinders.
Turns out the cap on the ignition coil hadn't seated properly, and the wiring plug into the coil had worked loose slightly.
So it's likely my swapping of the ignition coil caused the fault to move. And it was me that perhaps unseated them in the first place.
Luckily coils are relatively cheap (compared to injectors) but it's an easy one to check with the engine cover off (I leavre mine off now as it's a faff to remove)
Hth
Ian
bmwmike said:
g3org3y said:
What's the state of play with the N52 injectors, still v difficult to get hold of?
N53 injectors? They are easier to get hold of but have gone incredibly expensive at over £300 a pop each. I got a whiff that my 2012 may need a new set so i got rid; i'd had it 7 years so fancied a change too, but I knew the car well enough that there was a hint of trouble brewing. That said, apart from a set of injectors in 2015 (under warranty) and a Nox sensor it was a delight to own over the 7 years.Court_S said:
Looks like I might be joining the dud injector crew on my 335i (N54).
It struggles to start if left for a few days and it’s chucked up a misfire on cylinder six. It’s in for a service tomorrow and investigation into why it sometimes goes into limp mode on long trips, so I’ll ask BMW to check the injectors as well.
Possibly HPFP? I had the same on my N54 years ago and it was the fuel pump. It struggles to start if left for a few days and it’s chucked up a misfire on cylinder six. It’s in for a service tomorrow and investigation into why it sometimes goes into limp mode on long trips, so I’ll ask BMW to check the injectors as well.
So just as a quick update:
Firstly, some mentioned swapping coils, this was already done, whenever I’ve had a single cylinder misfire, my first point of call is always to swap coils and spark plugs over to rule them out.
The replacement injector arrived today and fitted it this afternoon (it’s a second hand one but has a 30 day warranty) and yes, I did put a new decoupler on it. I coded it in and reset adaptions.
It seemed to take longer than normal for cylinder 4 to kick into life and the engine to run smooth but there was likely to be fuel in the cylinder and the injector usually needs to sort itself out.
I then let the car run for about 20 mins with the odd rev to make sure it’s running fine on that injector.
As it was a cold start only fault, I’ll now leave the car until the morning to see if it’s still there. If it is, next point of call will be to swap injectors 3 and 4 over to ensure the new one isn’t faulty.
Firstly, some mentioned swapping coils, this was already done, whenever I’ve had a single cylinder misfire, my first point of call is always to swap coils and spark plugs over to rule them out.
The replacement injector arrived today and fitted it this afternoon (it’s a second hand one but has a 30 day warranty) and yes, I did put a new decoupler on it. I coded it in and reset adaptions.
It seemed to take longer than normal for cylinder 4 to kick into life and the engine to run smooth but there was likely to be fuel in the cylinder and the injector usually needs to sort itself out.
I then let the car run for about 20 mins with the odd rev to make sure it’s running fine on that injector.
As it was a cold start only fault, I’ll now leave the car until the morning to see if it’s still there. If it is, next point of call will be to swap injectors 3 and 4 over to ensure the new one isn’t faulty.
So to update following last nights post, started the car this morning and sure enough, it’s still misfiring on a cold start. So swapped injectors 3 and 4 around and it stays on 4.
Starting to really get confused with it now, when you first start it, it runs smooth for a few seconds, then misfires for a minute or two and then runs fine til it’s next cold start.
I pulled the below operational smoothness values whilst it’s misfiring and shows cyl 4 being a bit off but nothing horrendous.
Starting to really get confused with it now, when you first start it, it runs smooth for a few seconds, then misfires for a minute or two and then runs fine til it’s next cold start.
I pulled the below operational smoothness values whilst it’s misfiring and shows cyl 4 being a bit off but nothing horrendous.
Bimmerprofs website has really good info
Also N53 only monitors O2 on bank of 3 so if an injector is leakin and running rich the DME only sees the bank as rich so it leans off the cylinders iirc. So the misfire cylinder reported by dme is not necessarily the one with the leaky injector. Pull the plugs after it's been stood as I said further up and plug will be wet. Also likely more than one injector is faulty.
Also N53 only monitors O2 on bank of 3 so if an injector is leakin and running rich the DME only sees the bank as rich so it leans off the cylinders iirc. So the misfire cylinder reported by dme is not necessarily the one with the leaky injector. Pull the plugs after it's been stood as I said further up and plug will be wet. Also likely more than one injector is faulty.
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