Noob. Need help

[antonwba]

Hey guys I have a 87 325e. I think I'm missing some small module or sensor that's located on the side of the air filter box but I'm not even sure what's supposed to be there. Any help is appreciated.

[RobDog]

325e's have a small sensor attached to the side of the air box that senses altitude. The ECU can than adjust the fuel mixture for thinner or thicker air. I live at 5300 feet and the air is a lot thinner than at sea level. 325i's don't have the sensor on the side like 325e's, so you will need to find a 325e air box.

[antonwba]

I found what it's called, a barometric sensor. Are they interchangeable with like the 5 series 528e that also has the m20b27 engine?

[101]

yes sir. Having owned both a 528e and a 325e, they are indeed the same part.

[antonwba]

Ok so I sourced one off a 528e but it only has two pins on it. I had a broken meter on the 325e but it had 3 pins and the connector on the harness has 3 slots. The wires on the 325e connector are red/white, white, and orange. The wires on the 528e connector are just purple/brown and brown.

[101]

Hmm ... the Electrical Troubleshooting Manuals for a 1987 325e and a 1985 528e both show the same three wires going to that sensor ...

Red/White > ties into the positive from the fuel injector circuit
Brown > ground
White > pin 30 of the DME

What year 528e are you looking at? Do the sensors have part numbers visible?

[antonwba]

I don't remember what year the 528e was cuz it was from pick n pull. And I only have the part number off the one off the 528e. It's 0 280 110 006

[AndrewBird]

Use RealOEM.com to cross reference the part numbers.