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what are the possible suggestions that would cause surging and a large power loss...The engine code says fuel trim malfunction twice...

I have replace the O2 sensors..Throttle body gaskets...Intake manifold gaskets..Spark plugs....

I have checked the resistance for all six coil packs and they are all within specs....

would a weak fuel pump or a bad mass air flow sensor..... fuel pump was on the bottom side of the fuel pressure range but it is still within specs... did a pin-out for the mass air flow sensor and all checks and i also tested the film wire and it was good...all the test in the service manual...

Problems: Poor accelation.....surging during cruising speed, never had a problem with cranking or cutting off.....gasing to full throttle stops the surging issue but...still has a large lack of power......

keywords: bmw 325i, new bmw, bmw lineup 

I'm glad to see you put an effort into diagnostics here, despite not finding your bugs yet....

Is this manual or automatic transmission? There are automatic trans issues that can mimic your complaints.

Are there any other codes in the ECU? This is important. Also, please post your Additive (idle) and Multiplicative (part throttle) values.

Off the top of my head- fuel pressure- possible. Air mass meter- possible, usually causing lean running and pinging. The throttle positios sensor can cause headaches.

Are you experiencing a lot of oil consumption? These cars have an oil separator the can stick and cause high oil consumtion, and wierd running trouble with fuel trim issues.

Let me know- good luck!

keywords: bmw 325i, new bmw, bmw lineup