BMW 335xi/N54/E90 Misfires -- HPFP The Cause?

Hello,

So, here's my long, frustrating story.
*Keep in mind that, when reading, this is NOT negative talk about the JB4 tune.*


2007 BMW 335xi
N54 Engine.
68k miles.

I've had my car for about three months. Up until about a month ago, I ran the car with only a CAI mod on it. My car ran like a dream. Only once or twice did the engine have a misfire fluke when I "got on it". The SES light came on, and after 5min, it went away and the car ran like new again.

Well, about a month ago, I ordered the JB4 and put it on my car.

The first time I took it for a test drive (map 5), the turbos spooled up, and then *clunk*, I got multiple-cylinder misfire codes. I cleared them and did some more runs. I continued to get misfire codes, but the codes that came up with every run weren't being consistent.

Terry told me to switch it to map 1, and send him various CSV logs. With his help, we were able to get a consistent cyl4 misfire code.

So, I switched cylinder 4's coil with cylinder 1's coil. The misfire followed the coil to cylinder 1.

So, I bought a new coil and replaced cylinder 1's coil (originally cylinder 4's) with the new one. I took it for a test drive. The turbos spooled up, and then *clunk*, cylinder 1 misfire code...with a brand new coil in it.

I took the new coil off of cylinder 1, and swapped it with cylinder 2's coil. I took it for a test drive. The turbos spooled up, and the car actually responded without a misfire. However, when shifting, there was aggressive jerking -- as if the tranny was slipping or wasn't in sync. I came back and had zero codes...but the aggressive jerking stayed with the car for quite a while.

The next day, I took it for another run. The car ran perfectly. There was no jerking, no codes, no nothing. It was amazing.

The day after that, I was driving to work. I floored it, the turbos spooled up, and *clunk*, cylinder 5 and 2 misfire. I figured it was a fluke, so I just deleted them.
Took the car out again, and the same cylinders misfired. I deleted the codes and limped the car around until I had time to test it again.

Later on, cyl 2's misfire went away, and only 5 was still acting up.
I switched 5's coil with cyl 1. Cyl 1 started acting up.
I then switched out cyl 1's coil with the old coil that I replaced for the
new one. The misfires went away altogether...

Tired of running on luck, I decided to order new spark plugs. The plugs that were in it were still the OEM plugs...which means they had 68k miles on them.
I put in the new plugs, and put ALL of the old coils back on (setting the new coil to the side). After I started the car up, cyl 6 was immediately misfiring. I swapped that coil with the new one, and the misfire went away.

I took it for a test drive...the turbos spooled up, and then *clunk*, cyl 1, 2, 4, 5, 6 (or something like that) misfired.

Decided to say, "**** this. I shouldn't mod my car unless I can afford to fix it). Being a college student, I can't afford to fix it.
It made/makes zero sense to me why this tune works for everybody else, but not me.
Terry was nice enough to let me send the tune back and get a refund.


After doing some reading about the N54 engine, I came across an article that stated that the HPFP is one of the major flaws of this engine...and BMW warranties it up to 100k miles or 10 years. I figure if the problem is related to the HPFP and I can get it warranted, I could get the tune I want and be happy.

Does anyone have any ideas?


Any input is much appreciated.

Originally Posted by Hemorrhage

After doing some reading about the N54 engine, I came across an article that stated that the HPFP is one of the major flaws of this engine...and BMW warranties it up to 100k miles or 10 years. I figure if the problem is related to the HPFP and I can get it warranted, I could get the tune I want and be happy.

Does anyone have any ideas?

Yes: Get a lip lock on that bullet....bite.

Has the HPFP recall replacement & reprogramming been done? If not, visit your nearest
BMW dealer - this is a no charge thing.

If already done, take to a dealer for diagnosis & pay for repair.



You shall learn that these cars are not for the budget conscious or constrained.

Do you play the lottery? You may need assistance from parental units.

Not sure I understand that last statement.

Also...will they replace the HPFP even if the car is running trouble-free the way it is now?

Originally Posted by Hemorrhage

Also...will they replace the HPFP even if the car is running trouble-free the way it is now?

I didn't even carefully read the entire post, but yes they will replace the HPFP if it's an older version. My older one was still working perfectly, and in my mind, if it ain't broke don't fix it, but they convinced me to let them do it eventually.

BTW, I can respect all the enthusiasts with the tunes out there, who can also take more advantage of them by not living in CA and/or having higher octane, tires/suspension that can actually translate the power to the ground, etc, but there is something I'd like to say here, and I don't think I've ever said it before at this forum: One of the reasons I picked the 335i is precisely because I don't have to mod it in order to fly like a bat out of hell. It comes plenty damn fast out of the box. Sure I know it can go faster, maybe in fact I'll do stuff one day, but for now I'm still satisfied.

Originally Posted by Ilovemycar

I didn't even carefully read the entire post, but yes they will replace the HPFP if it's an older version. My older one was still working perfectly, and in my mind, if it ain't broke don't fix it, but they convinced me to let them do it eventually.

BTW, I can respect all the enthusiasts with the tunes out there, who can also take more advantage of them by not living in CA and/or having higher octane, tires/suspension that can actually translate the power to the ground, etc, but there is something I'd like to say here, and I don't think I've ever said it before at this forum: One of the reasons I picked the 335i is precisely because I don't have to mod it in order to fly like a bat out of hell. It comes plenty damn fast out of the box. Sure I know it can go faster, maybe in fact I'll do stuff one day, but for now I'm still satisfied.

They convinced you, huh?

So, I'm assuming that means the stealership won't just pretend to put one in since it isn't broken...

Originally Posted by Hemorrhage

They convinced you, huh?

Yes, that's what I said . . .

So, I'm assuming that means the stealership won't just pretend to put one in since it isn't broken...

I highly doubt it with the SIB on the form and everything, but at the very least, I'm sure the software was changed (if there wasn't a hardware changed for discussion's sake), because even the priming of the pump sounded different. (I assume one of the prominent sounds I hear when the car wakes up is just that, but maybe I've assumed incorrectly this whole time. As an aside, the owner at the most famous BMW indy shop near me said that priming of this pump upon waking began with some older 5 series, I can't remember which, was it the E39 or even older, I don't know).

Originally Posted by Ilovemycar

Yes, that's what I said . . .



I highly doubt it with the SIB on the form and everything, but at the very least, I'm sure the software was changed (if there wasn't a hardware changed for discussion's sake), because even the priming of the pump sounded different. (I assume one of the prominent sounds I hear when the car wakes up is just that, but maybe I've assumed incorrectly this whole time. As an aside, the owner at the most famous BMW indy shop near me said that priming of this pump upon waking began with some older 5 series, I can't remember which, was it the E39 or even older, I don't know).

Before making this thread, I read the sticky on this forum about the HPFP. The post dates back to 2011, and in it, they say that BMW has not yet fixed the problem, but has come out with a replacement pump.

Do we know if it has been permanently fixed, yet? Or are they just leaving the matter alone and just giving people the replacement pump?

Originally Posted by Hemorrhage

Before making this thread, I read the sticky on this forum about the HPFP. The post dates back to 2011, and in it, they say that BMW has not yet fixed the problem, but has come out with a replacement pump.

Do we know if it has been permanently fixed, yet? Or are they just leaving the matter alone and just giving people the replacement pump?

Ok, you only joined a couple of months ago, so I'll oblige you for one more moment. As far as I'm concerned, it's "permanently fixed". Sure, anything can go wrong, and I mean anything, but there is very, very, very, very little chatter about failing HPFPs now, and that really says something, because I believe when one does go out, you will read ALL ABOUT IT HERE.

Originally Posted by Ilovemycar

Ok, you only joined a couple of months ago, so I'll oblige you for one more moment. As far as I'm concerned, it's "permanently fixed". Sure, anything can go wrong, and I mean anything, but there is very, very, very, very little chatter about failing HPFPs now, and that really says something, because I believe when one does go out, you will read ALL ABOUT IT HERE.

I feel like I'm being referred to as a "use the search feature, idiot" guy :/.

I did read the sticky and I did search around, but I did not find a concrete answer...however, maybe my key words weren't the best ("misfire hpfp").


I'm at a loss. Hell, the situation even stumped Terry.

If the HPFP never got changed then yes it could be the issue. I guess its always a possibility, but if its missing so often spend the 100 bucks and let the dealer give it a shot. You seem like you know your way around the car, so it may comeback something you can fix.

Originally Posted by SuperTerp

If the HPFP never got changed then yes it could be the issue. I guess its always a possibility, but if its missing so often spend the 100 bucks and let the dealer give it a shot. You seem like you know your way around the car, so it may comeback something you can fix.

A little bit -- Still an apprentice/nooby. Been working at a garage for a little over a year, and I'm in college to get a degree in the automotive field. I'm determined to be a BMW tech.

I bought the car with 65k miles on it (CPO). Whether it has the original pump or not, I do not know.
Any idea on how to figure out if the new one is in it without having to take it apart?

I'd find out regardless after I take it to the dealer...but if it has the new one in it, maybe it'll save a trip.

Originally Posted by Hemorrhage

I feel like I'm being referred to as a "use the search feature, idiot" guy :/.

I did read the sticky and I did search around, but I did not find a concrete answer...however, maybe my key words weren't the best ("misfire hpfp").


I'm at a loss. Hell, the situation even stumped Terry.

I didn't mean to offend you in any way, and you did clearly state you looked through the sticky, and stuff. My reaction is probably more in relation to the amazing amount of FUD some older members like myself had to endure for quite a long time in years past. I'm not the only one who thought it to be way blown out of proportion, but I guess that's easy for me to say. But then, you know there are pro mechanics who are members here, and see a bunch of cars, and they might share the same opinion.

I only meant reply to the specific Q regarding the HPFP, and otherwise I am utterly unqualified to say anything about anything else in your post. Ok, besides one nit to pick, I think the HPFP is warrantied to 120k miles, not 100k.

Originally Posted by Ilovemycar

I didn't mean to offend you in any way, and you did clearly state you looked through the sticky, and stuff. My reaction is probably more in relation to the amazing amount of FUD some older members like myself had to endure for quite a long time in years past. I'm not the only one who thought it to be way blown out of proportion, but I guess that's easy for me to say. But then, you know there are pro mechanics who are members here, and see a bunch of cars, and they might share the same opinion.

I only meant reply to the specific Q regarding the HPFP, and otherwise I am utterly unqualified to say anything about anything else in your post. Ok, besides one nit to pick, I think the HPFP is warrantied to 120k miles, not 100k.

No offense taken <3.

The N54 doesn't have "occasional" mis-fire "flukes". If the motor had mis-fires previously it had a problem previously that needed a mechanic's intervention.

Originally Posted by tturedraider

The N54 doesn't have "occasional" mis-fire "flukes". If the motor had mis-fires previously it had a problem previously that needed a mechanic's intervention.

The first time it happened, I put a Verus on it.

It said, "Cyl 3 misfire when fuel tank is low."

The second time it happened, I never put a computer on it and cleared it.

It's been quite a long time since that happened.

Originally Posted by Hemorrhage

The first time it happened, I put a Verus on it.

It said, "Cyl 3 misfire when fuel tank is low."

The second time it happened, I never put a computer on it and cleared it.

It's been quite a long time since that happened.

Nevertheless, N54s do not have occasional mis-fire flukes. If the motor had mis-fires it had an issue that needed to be addressed. At 20 y.o. three months may seem like "quite a ling time". I assure you, it is not.

Originally Posted by tturedraider

Never the less, N54s do not have occasional mis-fire flukes. If the motor had mis-fires it had an issue that needed to be addressed. Three months is not "quite a ling time".

I never claimed it is normal that the engine has occasional misfires...hence the term "fluke".
I was merely stating what happened to me.

Originally Posted by Hemorrhage

A little bit -- Still an apprentice/nooby. Been working at a garage for a little over a year, and I'm in college to get a degree in the automotive field. I'm determined to be a BMW tech.

I bought the car with 65k miles on it (CPO). Whether it has the original pump or not, I do not know.
Any idea on how to figure out if the new one is in it without having to take it apart?

I'd find out regardless after I take it to the dealer...but if it has the new one in it, maybe it'll save a trip.

Yes the dealer could run the internal service report for you and if it got changed it would address it... Mine had two changed on that report

Originally Posted by tturedraider

Never the less, N54s do not have occasional mis-fire flukes. If the motor had mis-fires it had an issue that needed to be addressed. At 20 y.o. three months may seem like "quite a ling time". I assure you, it is not.

+1

OP - Call [email] to any dealer w/VIN will reveal whether HPFP recall was done. BMW dealers will do the recall on your vehicle regardless of need.

Problem appears to be HPFP cavitation due to partial press of some fuel components in the USA. Reprogramming the LPFP to maintain pressure on the HPFP suction side a textbook cure. HPFP replacement a premptive strike on damaged pumps. Experience shows this recall working, like, totally.

Whoever said they bought a 335i so he would not need to mod the engine, excellent! The differential and suspension, however, are badly in need of mods to make good use of the engine and generally put a lasting smile on yer mug. Believe it.

Well, I just called BMW.
They did a history report, and, apparently, my car already has the new HPFP in it...

So, I'm at a loss.

If I read correctly, you had multiple coils go bad. If that's the case, I'd recommend replacing all coils. My experience with bad coils is that the N54 does not always trigger a misfire code on the cylinder where the coil is in the early stages of malfunction.