I have a 2008 BMW 335I and the car has lost power on four occasions, while it was being driven. The dealer was not responsive to my complaints even after it spent over a month at the dealer in 2009. They kept saying the repaired the car, I would drive it home and then the next day when I went to start it the car would an engine failure light would come on and the car would shake terribly. The keep telling me it is the fuel injection and that has been replaced a number of times but I am fearful to drive the car on the highway in case the engine fails again.

- Darien , CT, USA

On July 24, 2010, my 2008 BMW 335I sedan experienced an hpfp failure in heavy traffic at highway speed. My 335I (delivered July 2008) has had long start cranks for at least one year. My Washington, DC BMW dealership has said it cannot replace the hpfp until it fails or throws an electronic code. On July 24, I was driving approx 500 miles to a vacation. 350 miles into the trip, on I-87 at approx 65mph in very heavy traffic, a car cut into my (middle) lane. I moved to the left lane and quickly applied medium throttle to keep up with traffic. My engine stumbled severely as I changed lanes/accelerated and the half-power engine light came on. The car began running extremely roughly, would not accelerate and lost speed rapidly, in the left lane of very crowded highway. The car behind me nearly rear-ended me. I shut off any accessories (air conditioning, stereo, etc.), pushed the gas pedal to the floor and was able to maintain approx 50-55mph on a long downhill as I merged over to the right lane and was able to get out of traffic. As I pulled off, the car neared a stall, with the engine idle jumping wildly. I turned the car off. A minute or two after turning it back on, the half-power engine icon came on again, along with a service engine soon light, and the engine again had almost no power to accelerate and ran roughly. The hpfp and lower pressure fuel sensor were replaced by keeler BMW, latham, NY, on July 29, 2010. My car had received the software update during a past service. I've known about the hpfp problem for several years. Because of the long cranks, I have been waiting for mine to fail and hoped it would not be in a dangerous situation. I noted a recent article in which a BMW spokesperson said the failures are not occurring at highway speed. Given my experience, BMW needs to be honest about this problem. I was driving at highway speed, in very heavy traffic, and feel fortunate to have come out without getting in an accident or worse.

- Washington, DC, USA

2008 BMW 335I infamous failing high pressure fuel pump (hpfp). Symptoms of a failing pump are long cranks upon start up and if it fails during driving, it can leave you stranded. My hpfp failed only once around 22,000 miles and was replaced promptly by BMW.

- Austin, TX, USA

I took the vehicle for the following symptoms: 1.) long(er) crank 2.) engine malfunction, reduced power 3.) service engine soon 4.) heavy, erratic shaking and shuddering 5.) engine sounded like a union pacific train with loud pumping sound 6.) because of 4 + 5, decide to turn-off the engine or sometimes it just stalls before 7.) after reset, the car becomes drivable but symptoms will reoccur. 8.) able to recreate problem when I mash the gas after doing some research on an auto forum, I suspected that the caused of the problem was a failing high pressure fuel pump. The dealership kept the car for 3 days to run some tests and concluded that the fuel pump was the problem. Since they replace the part, the car has not broken down again. However, they introduce another problems. 1) the car's exhaust noise is much louder now 2) the car is less fuel efficient, lower miles per gallon 3) the car now has a turbo lag which was previously non-existent. This means BMW is falsely advertising the 335I twin-turbo has zero lag. This was true before they updated the car's software but is not longer true at this moment in time.

- Dublin, CA, USA