Location of OXYGEN (O2) Sensor on 1986 325es

"Fred W" > wrote
> Floyd Rogers wrote:

>> Well, Fred, it's not likely to "throw codes" on a pre-OBD car. ;->
>> However, I agree about the vacuum leak. Ensure that the oil
>> filler cap and oil dipstick are firmly seated, too.
>>
> Are you saying the ECU will not generate a check engine light on a 1986
> 325es if the O2 sensor has gone tits up?
>
> Even the earliest Motronic ECU will show an O2 fault via the check engine
> light.

I usually associate "codes" with "OBD". BMW didn't have OBD
until '92, hence: no OBD ==> no codes. I suppose that this is
incorrect in a technical sense.

FloydR

"Fred W" > wrote in message
...
> >>My car's idle is not stable (it fluctuates b/w 800-1800 RPM) and I was
> >>told to replace the O2 sensor and it might fix the problem
> >
> That's nice, but we are talking about a 1986 (see subject line) and
> those are E30's (not E36's).
>
> However, E30's do also have ICVs, which is why the idle goes up and down
> when they have a vacuum leak.
> -Fred W
-----

I believe '86 was a cross-over year for the e30 6cyl engine controls. The
325es may have a separate ICV control box (green) in the glove box with the
ECU. In 1987 they ditched the separate ICV controller and integrated it into
the Motronic ECU. You may have it either way depending on manufacture date.
It's easy to check in the glove box, to be sure. If the ICV (under the hood)
has the 3-pin connector (square fuel injector type), the ICV is
Motronic-controlled. If there is a round 2-pin connector on the ICV, it has
a separate controller. Rule of thumb.

Bill in Omaha
'86 535i