Location of OXYGEN (O2) Sensor on 1986 325es

Does anybody know where the O2 sensor on a 1986 325es is? I tried looking under the area where the spark plugs are and could not find it. Anyone has seen a picture online anywhere?

I saw a picture of 1988 models (I beleive) which was on a really easy place to see but not my damn car.

Thanks for all your help in advance.

Reply to
bmwguy2
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Reply to
Dean Dark

Look in the exhaust pipe. They are never anywhere near the spark plugs.

Reply to
Fred W

According to the Haynes Manual I have here, the O2 sensor on an '86

325 is located just after the catalytic converter along the exhaust. Just out of curiosity, why are you trying to locate it? My O2 sensor on my '91 535 is placed right inside the catalytic converter, but the electrical connection is in the engine compartment.
Reply to
noobiedoobie

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

Reply to
bmwguy2

It might, but there's a whole better chance that it won't. When O2 sensors go bad they throw check-engine codes and the car idles very poorly, but genrally not where the idle races up and down. Your symptom sounds a lot more like a severe vacuum leak. Look around in the ngine compartment for a hose that has blow off or cracked or a cracked rubber intake manifold boot.

Reply to
Fred W

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.

FloydR

Reply to
Floyd Rogers

The E36 has a tendency to foul idle control valves. One that is not working correctly will cause an idle fluctuation. First you can try cleaning it by removing it and spraying well with throttle body/carburetor cleaner. If it is especially dirty and stuck you may have to replace it.

I had a really fickle E36 which required both an idle control valve and an airflow meter to stabilize the idle. Just be sure you have checked all the vacuum areas first.

Bob

Reply to
Bob Smitter

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.

Reply to
Fred W

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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

Reply to
Bill

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