p1250- manf. control feul air metering - United Bimmer Community

**fabian** · 11-23-2007, 11:05 PM

help i can not find anything on this code p1250 or po300b what is it
my car also came up with codes p1188 1189 and 1397

does anybody know

**Dudesky** · 11-24-2007, 06:30 AM

P1250: replace the fuel pressure regulator. Just as I suspected in the other thread.
PO300b: Don't know. Doesn't even sound like a valid code.
P1397: camshaft position sensor "B" circuit. If you have a CPS on both intake & exhaust, I would guess it's the exhaust side that's bad.
P1188/89: Fuel control, bank 1 sensor 1 & bank 2 sensor 1. I believe these should go away after you replace the fuel pressure regulator. If not, then you should move on to replace the O2 sensors.

My thoughts, which is in no way professional, but based on my previous experience of a similar nature: Your primary problem is the fuel pressure regulator. The diaphragm in it that holds back the fuel pressure has probably ruptured, causing the flooding of gas on your spark plugs and the cylinders. The other stuff happened as a result of that. If you continue running the car, you could be close to damaging the catalytic converter, if it hasn't been damaged already.

**Antiburn** · 11-28-2007, 07:55 PM

Im not sure how you guys interpret the fault codes but with a fuel trim fault I would check the intake boot off the throttel body. Theres a small off shoot that goes to your idle air valve and they always dry and crack and cause unmetered air leaks expecicaly on older car like yours.

As for your cam sensors, if your doing one, do the other. They sometimes go bad in pairs and are easy to do.

**TECH** · 12-03-2007, 10:47 PM

I'm not familiar with reading OBD codes, but I gather that it is a fuel metering fault, either rich or lean. The most common, by far, is running lean. Like mentioned above, check the "L" shaped intake boot tube that goes to the idle valve-they crack a lot.
Also, check that oil drain hose that goes from the bottom of the dipstick up to the oil seperator under the intake. If that hose is oily, it is probably leaking air into the crankcase. They break up at the top. You may need to take the airbox out to see it well, or crawl under the car. If those are ok, I'd suspect the pcv (oil seperator), or airflow meter.
Fuel pressure regulator is very uncommon problem.

**fabian** · 12-04-2007, 07:42 PM

thank you again for all the help

i went and found both boots behind {mas} to be bad so i fixed and still rough idle so i started looking at the crank case valve {pcv} and found a bad hose fixed it still rough idle now i am trying to remove pcv but before i go there is there any way to test it like a normal car

**TECH** · 12-04-2007, 09:29 PM

The rough idle can also be something totally different than what the lean mixture problem is. Do you have certain cylinders that are misfiring? A lean mixture from any of the issues mentioned, should effect all cylinders the same, not just one or two.
The PCV is a real pain to replace, and usually all those tubes get broken in the process. A slack-tube manometer can tell you if it's malfunctioning. We use a special tool that fits in place of the oil cap and reads inches of water.
Make sure the oil cap is seated good, as well as the oil dipstick. You can try spraying brake cleaner/carb cleaner around the pcv while it's running and see if it sucks it in and changes the idle.
If you notice a low honking noise if you quickly tap and let off the throttle, that valve is the cause of it.

**fabian** · 12-10-2007, 07:59 AM

finally fixed thanks for all the help it was the crank case vent {pcv} and wow what a nightmare to fix!!! but she is up and racing thanks AGAIN