[lilabanananose]

I've taken my 07 335i Sedan in several times in the last couple of months for a check engine light (the half engine check soon light). The dealer has not been able to make the problem go away.

The light will come on a I will lose power until the next time I start the engine. When I let it sit and start the engine again, the light is gone and power is restored. This means that if I don't go immediately to the dealer, that the light is not on when they get it. They've told me that data of the light going on and why is not stored, so they don't know where to start to find the problem. They also have trouble reproducing the fault and often give it back without any parts replaced, etc. Is it possible the vehicle doesn't record the instance of the check engine light going on and why??!!

Once, I brought it in while the light was still on and they changed some o2 sensors and turbo hoses. I'm just really surprised and frustrated that it has been so difficult to get a solution to my problem.

Anyone ideas/comments greatly appreciated!

[martho05]

I have a MY10 335i Coupe xDrive and I am having similar issues. The car starts running rough and Service Engine Soon light comes on. Shut it off for a few hours and it runs normal and light goes out. The dealer just replaced spark plug and ignition coil in cylinder #1 and a few days later - IT DID IT AGAIN! So far, there are no signs of an actual HPFP issue according to BMW. After owning the car for about 7 months, I am finding out that the N54 is really an unstable engine. I owned a MY06 330i Sedan with the N52 and never had a lick of engine trouble....

[lilabanananose]

Originally Posted by martho05

So far, there are no signs of an actual HPFP issue according to BMW.

I hadn't heard of the HPFP issue. Thanks. I looked it up and will be sure to ask my mechanic if that's a possibility.

Originally Posted by martho05

The car starts running rough and Service Engine Soon light comes on. Shut it off for a few hours and it runs normal and light goes out.

Did your dealer tell you the same thing that mine told me: that the fault light had to be on when you brought it in because they wouldn't be able to see why the light had been on previously? I really find that hard it believe.

[martho05]

Total garbage. All the fault codes are stored in the onboard computer. Have the dealer read the codes by connecting it to their scope machine and downloading them from your car.

[Chriztofor]

Originally Posted by lilabanananose

I hadn't heard of the HPFP issue.

lol lol lol we all wished we never heard of the hpfp issue.