tried to change the 02 sensor connector and now car doesn't start

[ogbimmer]

yesterday I bought a new o2 sensor. I took out the old one and put in the new one. I started the car everything seemed fine. I let it warm up then I went for a drive around the block. at low rpm it seemed alright but if I pushed the gas around 4500 rpm it would break up and hesitate. It did it a couple of times so I took the car back home. I also unplugged the o2 sensor while the car was running to see if the idle or anything changed and it was all the same. I looked at the connector on the wiring harness side and the plastic piece was broken and it looked like one of the wires wasn't connected so cut a new connector out of a parts car. I cut the old connector and hard wired the new connector to it and got in the car thinking I was good. I turned the key and no start. I will just keep turning and sometimes it will sputter alittle but never start.

any pointers of what to look at?
I am thinking about just buying a new harness.
Its my girlfriends car and I can't leave for the holidays till it runs again so I have a problem I need to solve sooner then later.

[dnguyen1963]

Buy a new sensor...

http://www.amazon.com/Bosch-13231-Ox...325i+o2+sensor

[ogbimmer]

the sensor is brand new. I just installed it yesterday.

the problem is on the receiving side of the o2 sensor connector.

[jlevie]

The break up around 4500 sounds like it could be a bad timing sensor or a fuel problem. Either could prevent the engine from starting.

[ogbimmer]

okay so I bought the electrical stuff to do the wiring perfect and got the car to start. There is still a breakup around 4500 though. I am thinking maybe the wires were on there way out when I pulled them off doing the spark plugs, maybe thats what the problem is.

[jlevie]

I can't see the wires on the O2 sensor connection being a cause of your problem. Something else is wrong.

[dashboardmonkey]

Unplug your dme and let it reset.

[dnguyen1963]

Unplug your dme and let it reset.

It is easier to disconnect the negative cable from the battery for about 10 min to reset the DME.

[seatown88]

I can't see the wires on the O2 sensor connection being a cause of your problem. Something else is wrong.

This.

The O2 sensor is not needed for the car to run properly. I would check fuel flow as a blocked fuel filter created a problem for me. After that, I would look for other possible loose connections in the engine bay, fuel injector harness specifically, but check them all.

[EREKSHUN]

why did you change the sensor in the first place? maybe it wasn't the issue. i had a similar scenario and it turned out to be the Crank Position Sensor. Basically once i hit a certain RPM (almost the same RPM every time). My M20 would lose almost all power and sputter. it would also cause a bad backfire sometimes almost like a loud POP! once i swapped my Crank Position Sensor my problem was fixed. i thought it was my O2 sensor, MAF, bad vacuum, i changed a ton of items and in the end it was a $10 part :) good luck E30 brotheren.


this write up should help you have a easy install.

http://www.pelicanparts.com/bmw/tech...aft-Sensor.htm

[FLG]

Crankshaft sensors are more like 60-70$ last I checked... Maybe more.

Go with ONLY an OEM sensor do not get any aftermarket. Had tons of issues with brand new aftermarket sensors.

Sent from my Galaxy Nexus using Tapatalk 2