02 E46 318i Low Power 1K-2K RPM Only (again) (N42 Engine)

[sPoNgE-SA]

I pulled this off another forum but this is exactly to the T what happends to my 2002 E46 318i.

I recently purchased a 2.0L petrol E46 318 Sedan, '02 with 140K KM/s.

The car hesitates under acceleration, in all gears, up to 2000 rpm, beyond which it is as smooth as it should be right up to the red line. Between 1000-2000 rpm the car bogs and kicks when put under heavy load. If you ask for light acceleration then it is not so bad but when you ask for some grunt it just stews.

I stuck it in 5th at about 1500 rpm and kept the accelerator pedal planted to the floor – after 5-10 secs of wallowing and kicking it actually cut out.With the pedal planted the needle was deflected fully as it normally is under full acceleration, however each time the engine dropped power the needle bounced back and forth to the 50-30 mpg sector. It seems that by command or otherwise the fuel pump was not supplying a steady stream of petrol. I’m assuming that it’s by command and some engine sensor is acting.

Also - the problem is definitely temperature specific - there is absolutely no problem when the car is cold and coming up to normal operating temperature. Once the temp gauge crosses the cold/normal threshold the problem kicks in and this division is quite noticeable. The worst it possibly behaves is when in slow moving city traffic when you would expect the engine to be at its warmest.

What I've changed on the car. Oxygen Sensor Exhaust, MAF tested and passed. New fuel filter, cleaned MAF, cleaned throttle body, replaced rubber seal on Cam Sensor on cylinder head, changed plugs, changed oil, changed air filter, checked ig coils, added fuel cleaner, used diff petrol, used injector cleaner, checked all pipes on engine that I know of and changed the intake pipe from air filter to throttle.

Car has been for diag tests and no faults are found.

Think that's all and I still have the problem.

[bcsa]

I'm experiencing exactly the same problems on my E46 (2003 318i). The problems already started at 60k-km's on the clock (now at 130k-km's). Each service interval under maintenance/service-plan, I asked BMW to have a look, but they only replaced Co's and MAF each time without any change to the problem.
Sometimes with the engine cold, at the first slow-stop in 2nd the engine would stutter severely and sometimes die (with a bit of rattling sound). I've found that a quick off-and-on of the ignition would fix the problem.

A specialist advised me to have a look at the Cam-adjustment motor, for quick responsiveness. I've also had the idea that the cat-converter was getting blocked up (if someone has already removed the cat please post a reply).

This problem is expensive to fix if the vehicle is not under service-plan and help would be greatly appreciated.

[DiarmaidGNR]

Originally Posted by sPoNgE-SA

I pulled this off another forum but this is exactly to the T what happends to my 2002 E46 318i.

I recently purchased a 2.0L petrol E46 318 Sedan, '02 with 140K KM/s.

The car hesitates under acceleration, in all gears, up to 2000 rpm, beyond which it is as smooth as it should be right up to the red line. Between 1000-2000 rpm the car bogs and kicks when put under heavy load. If you ask for light acceleration then it is not so bad but when you ask for some grunt it just stews.

I stuck it in 5th at about 1500 rpm and kept the accelerator pedal planted to the floor – after 5-10 secs of wallowing and kicking it actually cut out.With the pedal planted the needle was deflected fully as it normally is under full acceleration, however each time the engine dropped power the needle bounced back and forth to the 50-30 mpg sector. It seems that by command or otherwise the fuel pump was not supplying a steady stream of petrol. I’m assuming that it’s by command and some engine sensor is acting.

Also - the problem is definitely temperature specific - there is absolutely no problem when the car is cold and coming up to normal operating temperature. Once the temp gauge crosses the cold/normal threshold the problem kicks in and this division is quite noticeable. The worst it possibly behaves is when in slow moving city traffic when you would expect the engine to be at its warmest.

What I've changed on the car. Oxygen Sensor Exhaust, MAF tested and passed. New fuel filter, cleaned MAF, cleaned throttle body, replaced rubber seal on Cam Sensor on cylinder head, changed plugs, changed oil, changed air filter, checked ig coils, added fuel cleaner, used diff petrol, used injector cleaner, checked all pipes on engine that I know of and changed the intake pipe from air filter to throttle.

Car has been for diag tests and no faults are found.

Think that's all and I still have the problem.

I have the exact same problem on my 2000 318i,
Did you ever find out what the problem was?

[shadow333]

I had the exact same problem on my '04 318i. My problem was fixed when I replaced the Crank Position Sensor which is located below the started motor. It is not the easiest place to get to, but after a couple of cuts and bruises I managed to replace it. Car is running as smooth as a bimmer should.

[DiarmaidGNR]

Originally Posted by shadow333

I had the exact same problem on my '04 318i. My problem was fixed when I replaced the Crank Position Sensor which is located below the started motor. It is not the easiest place to get to, but after a couple of cuts and bruises I managed to replace it. Car is running as smooth as a bimmer should.

My car is fixed, it turned out to be the maf, it wasn't a genuine one so it didn't work right, I picked up a genuine one for about 200 euro from otto in tallaght.