Just replaced my HPFP (2009 335i) after 9400 miles. For the last few hundred miles the car would take longer to start (extended crank times to me). Worst case was about 15-seconds. Called my SA and he said unless the car threw a code, he could only do a software update to lower the pressure on the pump. So I waited. About a week later while I was driving, the car went to reduced engine power (that yellow half-engine icon). Wow! What a difference in performance. I was on my way to the airport and was stopping for coffee anyway so the car got a short break while I grabbed a cup. When I restarted, the icon was gone and car was its normal self. Called the dealer who promptly scheduled me in when I returned from traveling and gave me a loaner. Code dump showed HPFP problem. They reprogrammed the car and did a cold start the next morning. It wouldn't start properly. BMWNA authorized the new HPFP and software update. SA tells me the software reduces the pressure of the new pump so it does not self-destruct but does not negatively affect performance. His take was the pressure is set too high from the factory. So far, so good. Car starts in less than 1 second, has no problems lighting up the tires and quickly throws me back in my seat under heavy acceleration. Kudos to Paul Miller BMW (Wayne, NJ). They still have a very happy customer.
Your experience is quite common. BMW is using the software upgrade to cycle the low pressure electric fuel pump longer to pressurize the fuel system including the HPFP. Your SA is incorrect about lowering the HPFP peak pressure. The issue is when the HPFP begins to fail it will no longer hold the proper fuel pressure when the vehicle is shut off for long periods of time like overnight. When you go to start the car in the morning the failing HPFP needs to build pressure in the entire system that has dropped overnight because the HPFP didn't hold the pressure it should. With the HPFP failing it takes longer and longer to build the proper fuel pressure to spray fuel into the cylinders. The new software is a crutch to try and compensate for the failing HPFPs. It appears that BMW still doesn't know what causes the HPFPs to fail. Restarting the car will often but not always reset the limp mode dash symbol and vehicle operations but it tends to reoccur shortly thereafter. It's an unsafe and bad situation for all.
Interesting. But maybe lowering the peak pressure saves on the the pump wear, thus lengthens the pump life. Everything you say makes sense (and I've always gotta take the OEM-speak with a grain of salt). I gotta say the lower pressure part makes some sense as well. Too bad BMW hasn't figured out a solution given that we're 4-years into this engine.
The HPFP peak pressure is a requirement to inject the correct volume of fuel based on engine demand. You can't just lower the peak pressure as the pump can't deliver the fuel volume required in the time span it has to deliver the fuel. SA's rarely get the full story on engineering changes or don't completely understand the changes. The factory is not overly free with engineering info. either.
3 HPFP's and counting I just bought a 2007 335i Coupe, and had BMW run the VIN for the service history before I purchased it (from an Audi dealer) and the only issue the car had in 49K miles was 1 HPFP every year, last being in 10/2009 at 46K. Now, would this latest service of the HPFP be the New Software Update? Its got a warranty for 120K miles, so no worries there, just curious... It does seem very bad on BMW's part to have an ongoing issue with this one part for 4 years, sometimes it makes you wonder, why they cant resolve it....
BMW updates software regularly to try and fix/patch issues. The latest N54 software I've seen was in the last month or so to cycle the low pressure fuel pump longer. The 10/09 software is not likely be the latest software. The extended HPFP warranty is nice but it doesn't address the safety issues with the sudden loss of power, engine stalling or being stranded on the side of the road any time of day or night.
Since my pump was replaced, the engine ignites in under a second after hitting "start". I just got back to the airport today after 4-days of travel. Pressed the button and it started like I had just turned it off moments earlier.
BMW has a new HPFP out as of two weeks ago. Part number ends in 933 and is a rebuilt, not new HPFP. This is what the dealers are installing now. No more 943 HPFPs shipping to dealers. The 943 HPFPs lasted about four months before being superceded by the 933 pump. I believe the 933 is HPFP version six?
335i power down Since the replacement of the HPFPump and computer software update, the car seems to be less responsive and down on horsepower although it starts and runs well and fuel economy has not suffered. Anyone else notice this?
I have gotten mine replaced last week, and haven't had any problems so far with power or start up. My engine knocks too much for my taste when in park...Not really sure what that's about, but it was happening before the HPFPump replacement, and still happens after a oil change and spark plug replacement.
Well it is definately a frustrating situation. I just picked up my car and it seems to be running fine. I have been having the same problem as described here. It started with just long cranking times in the morning or after a long day at work, then the engine malfunction light came on. I usually just turned the car off and restarted it and the problem would not persist. This last time the problem occurred on the morning of the day I was taking the car in to have this checked out again so I did not restart it, because I wanted them to see the malfunction light. Boy, was the performance of the car really diminished! I had no power when I tried to accelerate on the freeway. It was really anemic. I love to drive this car when it is working fine, but having this problem is troubling to me. Especailly have to have the pump replaced a second time. and have a low pressure sensor replaced on another occasion. I agree, you do not expect so many people to have this problem on a car that you pay so much money for. But I am glad that it is not just my car having the issue. Hopefully BMW can sort through this, but I am definitely contemplating not keeping this car past it's warranty period or opting to get an extended warranty.
It is a great car when it's running properly but you never know when that will be. Many people have dumped the x35i models because they are so unreliable. Consumer's Union and Edmunds have both panned these models for reliability issues. If you can't go on a trip or plan on arriving at the airport on time because the car is unreliable, why deal with such foolishness?
BMW is buying time I heard BMW is buying time with the latest software and HPFP replacements, they basically detuned the cars until the new pump design comes out. My car was basically in service for 6 weeks or 4 tries to fix my issues. Now its slow as hell, the top end is gone. Before I did Dinan, my HP at the wheels was 267, with dinan it was 321, now back to stock with the latest software, its 227. They took 40HP from me and the gas mileage went from 22 to 19. Mazda got sued for misrepresenting the HP for the RX-8 and I think we would have a case against bmw. Any lawyers out there
Does anyone know what the software update changes? I've just got my '08 335 w/manual xmission back from the dealer after they 'updated' my software to correct a 'long start' issue. This is the 2nd time in for that problem. Last year I took the car in for the same problem and they replaced the hpfp. I've only driven the car a few miles since I got it back but it seems less responsive to throttle inputs than before the update.
Unfortunately numerous people in other forums are reporting a loss in power and driveability with the latest software upgrade - similar to a previous version that resulted in numerous class action lawsuits that are pending. The new software cycles the low pressure fuel pump longer before you start the engine to pressurize the fuel system quicker. This appears to be to compensate for the fact that the HPFP doesn't hold the system pressure that it should, which can result in long cranks. It really doesn't look like BMW has identified the root cause of the N54 HPFP or fuel system issues even after four model years?
ForcedInduction, Thanks for the reply. I guess I do not understand why the software change you describe would affect throttle response. I am not disputing your response, I simply can't connect the cause-effect dots. I will drive the car some more, but my initial unscientific impression is the instantaneous acceleration at low RPM I used to get comes later in the RPM range. Does that make any sense?
By changing the boost pressure or cut-in point BMW can alter the engine power curve. BMW did this once before to try and eliminate wastegate rattle on the N54 engines. The software can change a lot of operating parameters. The one I mentioned about the low pressure fuel pump operation is the current crutch for a failing HPFP. That is the main reason for the software update but you are not alone in reporting a power loss after the update so it's likely BMW is back to dropping boost/power without telling customers. One person dynoed his car before and after and saw something like a 40 HP drop after the latest software was installed????????
Well, my 08 E93 is at BMW of Fairfax to have the hpfp replaced. On the beltway the reduced power/ engine malfunction light came on. Talk about reduced power! I've had the long cranking issue for two months now. But I turned off the engine, restarted and it was fine. This time though it happened on the beltway around DC at rush hour. Not a happy camper right now. Also had the rattling sound (sounded like loose muffler or cat converter heat shields). Came from the rear end. They said my 335i would be ready on tuesday. That's five days in the shop. I do have an 08 four door 335i loaner though. this car will snap your head into the headrest. My E93 does not feel like this. Wonder what the difference is?
Another HPFP I just had the second HPFP replacement at 22K. Classic symptoms of long crank at start and then failure in a few days. The car has now been repaired under warranty, but the loss of original responsiveness and power continues. This car before the first HPFP failure and replacement at 7K was a totally different animal . I think that currently a 328i is not far off the power of this allegedly 300HP car. This is my 13th BMW and I am thoroughly unhappy with this state of affairs. BMW ought to be ashamed of their lack of candor and lack of engineering on this engine/car combo. I have read the Arkansas Federal Complaint and think it is well taken.
