Error Codes?

[paulyf21]

My 99 323i has been running rough lately. My wife got some gas at a gas station that shes never been to and put regular in and now the car runs horribly! When the car is at idle it stumbles and puts. Theres a knocking noise coming from the engine at start for about a minute then stops. Occasionally the car stalls. When I put it in drive and go the car runs fine. I changed the oil,air filter, fuel filter and replaced the spark plugs. Car still runs rough but not as much. I took it to auto zone and had the codes read.
In Order:
p0300 Random Misfire
p1250 Fuel low
p1189 O2 Sensor Bank2 Sensor#1
p1188 O2Sensor Bank#1 Sensor#1
p0301 #1misfire
p0305 #5misfire
p0303 #3misfire
p0306 #6misfire
p0302 #2misfire
p0304 #4misfire
p0170 fuel trim Bank#1 Malfunction
p0173 fuel trim Bank#2 Malfunction
p0300 Random Misfire
p1250 Fuel Low

Help Please
My fellow work says he thinks its the fuel pump. He said theres way to test without removing the tank. If anybody can help please let me asap
thx
Paul

[Jeron]

Low octane should not cause any noticeable issues. Bad gas maybe but thats very rare.

Fuel pump maybe but fuel pumps usually fail completely.

I would start with fuel filter and fuel pressure regulator if they are old I would replace them. If they are not old I would do a fuel pressure and flow volume test.

There is no reason to drop the tank, the pump is under the rear seats.

Oh, you just replaced the fuel filter. IIRC, on the early E46 I the fuel pressure regulator is separate from the filter.

[paulyf21]

The fuel pump is under the seats and not in the tank? Does that mean it is an 'in-line' pump? Or is access to the tank also under the seats?

If it is an 'in-line' fuel pump, should there not be a 'filter' or a fuel pump 'pick-up screen' on the suction side of the pump? Or perhaps some other kind of filter (besides the actual fuel filter that is between the pump and the fuel rail - which I have replaced).

Perhaps it is clogged or dirty? My fellow worker says from the CEL codes that it seems like there is not enough fuel pressure or flow to the injectors.... that this is causing the misfiring and not bad octane.

Here in NJ, gas stations are very well known to have 'dirty' gas from lots of sediment in the gasoline itself.

Also, what is the procedure for checking pressure and flow myself? Is there something you might be able to post or a link to follow towards some instructions?

Thanks for your help

[Jeron]

The pump is in the tank and the tank is under the seats. There should be a plastic mesh around the pickup.

Pressure test requires a pressure gauge and fittings which you can buy as a kit. Flow requires pulling a line and measuring volume pumped per minute. Shouldn't be too hard to find instructions on the web.

Like I said above, your fuel pressure regulator is not integrated into the fuel filter therefore you need to change it separately. At this age, putting on a new pressure regulator would not be a waste for the same reason you replaced the fuel filter. It fits your symptoms.

http://www.realoem.com/bmw/showparts.do?model=AM33&mospid=47718&btnr=13_0737& hg=13&fg=10

[paulyf21]

Last night I replaced the coils. But the car is running horribly. I really dont know what else to do.

[matthew-s]

You live in NJ? Your wife did not happen to get gas from Lukoil did she?

Kinda old news - but they left a lot of people stranded.