[chrismanchr]

ive got exactly the same problem changed the plugs and coils no difference ,i got a yellow engine light up for about a week but while the light was up it ran great ,it went out and went back to its stuttering jerky self ,cleaned the maf etc ,i'm gonna have to bite the bullet and take it to a bmw specialist ,i hate paying for labour !

[BRGmatthew]

Originally Posted by chrismanchr

ive got exactly the same problem changed the plugs and coils no difference ,i got a yellow engine light up for about a week but while the light was up it ran great ,it went out and went back to its stuttering jerky self ,cleaned the maf etc ,i'm gonna have to bite the bullet and take it to a bmw specialist ,i hate paying for labour !

Yeah, I did the same. I disconnected the MAF for a while. Car ran just fine. Cleaned the MAF, put it back on, plugged it back in. Same thing happened, jerky and weird. Took it to the dealer. They said it was because my intake and exhaust is causing my MAF to read too much airflow. I connected my own OBD2 scanner and it says my engine is running lean.

[temporarychicken]

Interestingly, on the E90 series with the N52 engines, the MAF sensor is not a primary sensor.

On older models, the MAF was critical to measuring input airflow, and the output from the maf fed directly into the fuel calculation.

It seems now that on the E90 N52 cars, that the MAF is just a secondary sensor, and the output from it is only used for minor trim changes from the basic fuel map.

So when you unplug it, the ECU just goes to using default values which were hardcoded from new, and although theses values are not optimal for economy, they sure seem to be for power, since the car went like new when the MAF was disconnected.

However, drive it without a MAF for more than a minute and the DME will throw a yellow CEL on the dash since it's not heard from the MAF for a while.

I've ordered a cheap cable from Ebay to see if I can't access the history of fault codes...

[Three_thirty_I]

Resurrecting this thread since I am experiencing some of these same problems to a certain degree and already been busy replacing things without any change, annoyingly! I do feel that the BMS PBX aggravates these problems, but not cause them if that makes sense.

The biggest issue that I am having at the moment that I am trying to solve is the pinging or knocking between 1800 and 2500 rpm, mostly at moderate throttle inputs, but have noticed it on gear changes when driving a bit more spiritedly. So very annoying! And also have that dull performance drop off from 3000 - 4500 rpm before the power comes back like crazy! Hesitation has been there from day one and very irritating, and certainly not something that I would have expected from a BMW!

Today I tested something out (did something that I have indirectly trained myself not to do), I mashed the throttle while in 4th at around 60 - 80 km/h and get that sudden hesitation. Try it again soon after and it's fine, but let the car settle and maybe try 5th gear and again, mash the throttle and there's that somewhat violent hesitation.

Engine also feels lumpy to me - off throttle and there is an overrun jerk, then gently feed power back on and there is a slight jerk, so not the refinement that I want at all. Bought some Liqui Moly injector cleaner which I am going to try out and see, but I somehow doubt that this is going to help, and I am really now getting to the end of my patience with this car!

[MrQuickR1]

Originally Posted by Three_thirty_I

Resurrecting this thread since I am experiencing some of these same problems to a certain degree and already been busy replacing things without any change, annoyingly! I do feel that the BMS PBX aggravates these problems, but not cause them if that makes sense.

The biggest issue that I am having at the moment that I am trying to solve is the pinging or knocking between 1800 and 2500 rpm, mostly at moderate throttle inputs, but have noticed it on gear changes when driving a bit more spiritedly. So very annoying! And also have that dull performance drop off from 3000 - 4500 rpm before the power comes back like crazy! Hesitation has been there from day one and very irritating, and certainly not something that I would have expected from a BMW!

Today I tested something out (did something that I have indirectly trained myself not to do), I mashed the throttle while in 4th at around 60 - 80 km/h and get that sudden hesitation. Try it again soon after and it's fine, but let the car settle and maybe try 5th gear and again, mash the throttle and there's that somewhat violent hesitation.

Engine also feels lumpy to me - off throttle and there is an overrun jerk, then gently feed power back on and there is a slight jerk, so not the refinement that I want at all. Bought some Liqui Moly injector cleaner which I am going to try out and see, but I somehow doubt that this is going to help, and I am really now getting to the end of my patience with this car!

07 328 e90
It's the characteristic of the car.....
At least that's what I've been told from the dealer.
I have the powerbox in as well and it does amplify the effects, I have to keep it on stock map for now so it's not as bad, but still is.
I have changed out the plugs, coils, MAF, air filter, had the fuel pump checked, fuel sending unit checked, fuel injectors checked, and then some, I had been leaning towards the gas pedal position sensor, maybe something to do with the stability control sensors, or just a bad throttle body.
I'm tired of dumping money and time into this car. If it weren't for my commute, I would go back to Dodge trucks.
At first I suspected a bad powerbox, it happens, but BMS responded back to me with such a shitty response saying to get a 335. Then asked if I installed it right. Hello, I'm not an idiot! Perhaps they are with their instructions, a couple of pin numbers to connect the wires to said it was one color but it wasn't the color in the car as they said it was. I connected it to the pin number. I then questioned myself if that was right, so it has to be something else, it's just a damn mystery.

[Phil325i]

Have you tried throttle pedal re-learn procedure? Just a thought as you're clutching at straws...

[Three_thirty_I]

Originally Posted by MrQuickR1

07 328 e90
It's the characteristic of the car.....
At least that's what I've been told from the dealer.
I have the powerbox in as well and it does amplify the effects, I have to keep it on stock map for now so it's not as bad, but still is.
I have changed out the plugs, coils, MAF, air filter, had the fuel pump checked, fuel sending unit checked, fuel injectors checked, and then some, I had been leaning towards the gas pedal position sensor, maybe something to do with the stability control sensors, or just a bad throttle body.
I'm tired of dumping money and time into this car. If it weren't for my commute, I would go back to Dodge trucks.
At first I suspected a bad powerbox, it happens, but BMS responded back to me with such a shitty response saying to get a 335. Then asked if I installed it right. Hello, I'm not an idiot! Perhaps they are with their instructions, a couple of pin numbers to connect the wires to said it was one color but it wasn't the color in the car as they said it was. I connected it to the pin number. I then questioned myself if that was right, so it has to be something else, it's just a damn mystery.

Just out of interest. I finally had my car checked with a tuner's diagnostics machine which apparently pics up quite a bit more information than the standard diagnostics machines at most agents, and they took the car for a drive while the diagnostics was being read, so basically a live read of what was all going on. This is what they found.

Engine is not pinking, the DISA flaps are fluttering and making constant corrections but incorrectly which is causing the pinking type noise and causing the engine to run less smoothly overall. Then more worryingly, the thermostat is not working properly and forcing the engine to run too cool, so there is some over-fuelling going on, especially on colder days. The Valvetronic motor is apparently 10% out of spec, not too sure what that means, but apparently can be sorted out with software, also not sure - ECU flash?! Cylinders 1 and 5 have some strange injector / valve behaviour, so either those injectors aren't working properly or the valves are not seating correctly - but this will need further investigation.

The first thing that needs to be done is to replace the two DISA flaps and the thermostat - then run tests again to see if this solves the problems.

At least now I know I am not imagining things!

[Three_thirty_I]

Of course, agents wanted the car so that they can run diagnostics themselves and surprise surprise, they found no errors. So clearly I am just imagining this and the independent tuner is just guessing... Maybe time for me to move on!