BMW N53 P0306

[sajn]

THi and welcome everyone so glad to join forum.

I have bmw n53, 2007 which is driving me slightly mad.

Summary of story: The engine started rough idle and multiple cylinder misfire with lack of power, so replace 6 injectors, 6 coil packs and 12 spark plugs {6 before injector replacement and 6 after injector replacement) alon with maf sensor.

Currently vehicle has no more codes except P0306 which is cylinder 6 have swapped injector 6 with injector 2 and no difference in code.

I have picoscope 2202 with a 20:1 attenuation adaptor and back probes, i am waiting for delivery of hanteck ht25 probe so i can compare injector to exhaust.

The misfire only occurs when vehicle is warm, so from my diagnosis the only items left are dce (ecu), wiring loom also could the disa valve am open to help and advice ?

Also am new to picoscope so some tips and advice appreciated.

[Iver]

Strange misfires with these engines are well documented on this forum.

Here is a Peugeot (with a BMW Setup) so could be relevant !!

topic23151.html

Try disconnecting the Valvetronic and or Vanos to promote change.

Another one
topic22262.html

[sajn]

Update on cylinder 6 misfire P0306:
So used the picoscope for 1st time am new to using picoscope and last time i used an oscilloscope was in college days.
I checked signal on cylinder 5 and 6 coils, then i measured signal on injector 5 and 6, used hanteck ht-25 on exhaust as well, from these it looks like ecu/dme is sending correct signals.
I attach screenshots and psdata files.
So my next suspicion could be the one of the following;
1) Stuck disa valve although no error messages for this
2) Valve spring broken need a compression test followed by cylinder leakdown test for this.
3) Vaccum leak on intake
4) High pressure fuel pump

Any more tests i can perform to narrow down ?

[sajn]

N53 does not have valvetronic is direct injection

[sajn]

Quick update
After setting up inpa deleted all adaption values and errors after as lots of error mesages came up, no longer had misfire on cylinder 6, had error p0030 which is lamda sensor pre cat, replaced bank 1 and bank 2 sensors, car is better but now getting p0174 which is running too lean, when reset works for a while, could hear whistling noise on engine so looking at getting smoke test as suspect valve cover or hoses have air leak. Following each code systematically.

[tintoverano]

N53 does not have valvetronic is direct injection

how are the two connected?

it does have both valvetronic and vanos

[sajn]

N53 does not have valvetronic is direct injection

how are the two connected?

it does have both valvetronic and vanos

The n52 has a valvetronic motor and the n53 does not have this

[liviu2004]

N53 does not have valvetronic is direct injection

how are the two connected?

it does have both valvetronic and vanos

Not acc wiki. What are your sources that it has valvetronic?

[sajn]

Both models have valvetronic although n52 has valvetronic servo motor which caused a lot of issues and was then removed on n53