Running Rich

[Filthy1001]

Hi
I just recently purchased a 93 325i and have been having a few problems.
The car seems to run fine when cold but when at full temperature there seems to be a lack of power and the car seems to hesitate.
I got the air filter,plugs,oil and oil filter changed when i first got the car at a garage...anyway,ive just checked the sparkplugs which have only done a few hundred miles and theyre black with soot, im not very mechanically minded but even i know this means the car is running way to rich.
Any ideas whats making it run rich? After reading many posts on the forum i get the idea it might be the O2 sensor?
But would this also not effect the car at idle as the car idles fine?


any suggestions most welcome

[Jared at Pelican Parts]

Sounds like the O2 Sensor. How many miles are on the car?

[Filthy1001]

Thanks for the rely....there are 99k on the clock.

[Jared at Pelican Parts]

SOunds as though the O2 Sensor should be changed at this point

[blkongry]

Yeah, I'm thinking O2 sensor also. The O2 sensors don't usually 'go bad' per say, but rather they get coated and clogged, reducing their ability to read the changing exhaust mix. This is something that probably wouldn't even be noticed at idle, but would be noticed under load and with soot forming at the exhaust (not to mention sooty plugs).

[supertack]

For all us 'stu-nods' out there, where is the O2 sensor located, & how would you go about changing it out?

[Jared at Pelican Parts]

The O2 Sensor is typically located in the exhaust manifold down near the bottom of the car.

[Filthy1001]

Cheers for the advice
I think ill get the local garage to replace it for me as ill probably make a hash of it. I think you need a special tool to do the job aswell.

[Jared at Pelican Parts]

Do it yourself, it's beyond easy... Check this out...

http://www.pelicanparts.com/bmw/techarticles/E30-O2_Sensor/E30-O2_Sensor.htm

[Filthy1001]

Thanks for the replys guys....well, i changed the 02 sensor today,fairly easy job and what a difference
Car now runs great, no more hesitating,and a lot more responsive and willing to rev right up to the red line.
Me a happy bunny.

[Wayne 962]

Cool deal, a success story!

-Wayne