[Modmike]

My car had the new HPFP and injector change in 2011 and in the last 6 months I:

1) Changed the cam position sensor
2) Replaced plugs and coils
3) Changed Vanos
4) Replaced water pump and thermostat
5) Replaced oil housing seals
6) Rebuilt the Mechatronic with all new solenoids and sonnax kit

The last part I just did because of rough and odd shifts.

The weird surging or stumbling at 1500 RPM started after I did the water pump and thermostat last month. Seeing as I still had the problem after the transmission mechatronic rebuild, I did the reset, multiple times, to no avail. Every reset made the issue almost disappear, only to come back within a day. Strangely, the mechatronic rebuild did not fix most of it's odd behaviours.

I decided to clean the MAP sensor (vacuum not T-MAP which is for boost pressure) and when I pulled it, it was covered in oil and carbon. I used MAP cleaning spray, re-installed, and went for a drive. What a difference! I forgot what smooth power felt like!

I still have a bit of an issue so I ordered a new one that I am waiting on. I am not saying that this is everyones problem, but the symptoms are classic MAP sensor issues, especially high fuel consumption.

Try cleaning yours first to see if it improves your issues, if it does, then replace it.

[jwebb335xi]

Originally Posted by Modmike

My car had the new HPFP and injector change in 2011 and in the last 6 months I:

1) Changed the cam position sensor
2) Replaced plugs and coils
3) Changed Vanos
4) Replaced water pump and thermostat
5) Replaced oil housing seals
6) Rebuilt the Mechatronic with all new solenoids and sonnax kit

The last part I just did because of rough and odd shifts.

The weird surging or stumbling at 1500 RPM started after I did the water pump and thermostat last month. Seeing as I still had the problem after the transmission mechatronic rebuild, I did the reset, multiple times, to no avail. Every reset made the issue almost disappear, only to come back within a day. Strangely, the mechatronic rebuild did not fix most of it's odd behaviours.

I decided to clean the MAP sensor (vacuum not T-MAP which is for boost pressure) and when I pulled it, it was covered in oil and carbon. I used MAP cleaning spray, re-installed, and went for a drive. What a difference! I forgot what smooth power felt like!

I still have a bit of an issue so I ordered a new one that I am waiting on. I am not saying that this is everyones problem, but the symptoms are classic MAP sensor issues, especially high fuel consumption.

Try cleaning yours first to see if it improves your issues, if it does, then replace it.

MAP in charge pipe to throttle body???

Thanks for the write up!

[Modmike]

No, thats the TMAP. The MAP is a vacuum sensor on the top of the intake manifold near the windshield. I will try to add pic tomorrow.

[335e92tx]

Actually, there is a vid that you can just disconnect the map for a period and see if idle/driveability improves and that can be just as informative. TMAP cannot be disconnected (and the engine run) and is normally more directly involved with hotwires having deposits. I ended up trying both (replaced the TMAP), didn't fix my surge (of which can be many causes as these things age).