Did Fuel filter & O2 sensors today

The Bosch O2's I got off Amazon are identical to the ones that came out, which were factory units at 101,032 miles. While I was there I replaced the small section of vacuum hose that goes to the air pump valve. It was rock hard and crumbly. Took me about 30-45 minutes to do both sensors and the vacuum line. Torqued them to 35#'s being I had the offset ratchet adapeter on it.

Then I did the fuel filter. Took my time, ended up only needing to run out and get 1 hose clamp. Only one hose did not have a screw type clamp. Damn factory crimp clamp was the hardest part, getting it off. Hoses are in great shape. Filter was original BMW. Ovoiusly never serviced due to the crimp clamp. I shook the crap out of it and quite a bit of debris came out. Nothing huge, but just a ton of very small particles. Looked like dirt or something. MANN w/regulator went back in. Good for another 100k. That is one big filter.


Then I degreased the engine compartment and front end underside while I had it up on stands. Can't wait to take it out for a actual cruise. Seems like it's running perfect.

I bet you'll enjoy the drive.

I replaced my fuel filter last weekend. I didn't expect to notice a difference, but I believe the car runs better. I drove it on a 500 mile round trip during the week and the OBC reported 29.7 mpg. That's up from 28.4 mpg on my last trip.

I replaced the oxygen sensors last year at about 110,000 miles. That made a huge difference in engine performance,but I expected that.

Good to know.... b/c my laundry list of things to do is shrinking and I'm trying to get it to a solid 30MPG hwy car. I'm around 26-29 right now depending on speed and a/c or not. Gear box oil is next.

I have a pair of long-handled diagonal cutters that is effective against the crimp hose clamps.

Yes, you need long handled ones. I was using a almost new pair of standard Channel lock dikes and could not cut it. Ended up basically taking it apart carefully.

"dikes!" You're an old-fashioned mechanic. Only old turds use that term.

haha. I'm only 29 but have been a gear head for a long arse time. And I came up through the old school domestic scene but quickly diversed myself into the Supra scene, then rock crawling, and for the past 3yrs the BMW scene.

Please post back on any changes to your gas mileage and any difference in engine response, post-O2 sensor change. I found a 5% increase in gas mileage (based on hard numbers) and a little smoother engine response (which was a bit subjective) after changing my O2 sensors. This was a pleasant surprise.

Will do fudman. I only changed the front 2.

Originally Posted by FLE39

Will do fudman. I only changed the front 2.

The front 2 were the ones you needed to change unless there was a code for the after catalyst sensors.

^ Agree. No codes present, hence why I only did the 2 fronts. the rear 2 are just there for big brother to make sure you're cats work. Do not plan on tampering with cats ont his car. I want it 100% legal. Even my window tint meets FL law. If I did anything it would be a cat-back. But on this car not even sure if it's worth it.

Update- Drove it for the first time after the noted work and all I can say is wow. The engine is so much smoother. Haven't gotten on it yet. Averaged about +1 mpg better than normal on my to work commute. And it's colder than normal out. 50 Vs 80. But the biggest noticable difference is the smoothness of the engine. Feels like someone turned the clock back to 40k or something. normally I don't notice a difference on fuel filters and O2's. But then again, normally I'm not working on such a old high mileage car. Hard to tell which item is making the biggest noticable difference being I did both at the same time. Oh well.

Been meaning to do the O2' myself. Thanks for the heads up that only front 2 really need the change out. Did you need special tools to remove it?

http://www.amazon.com/Bosch-13477-Ox...gen+sensor+e39

Is that who you went with at 48 ea? Autohausaz has the same ones for 65, but never went amazon for parts before.

^ Yes got mine off Amazon for $48/ea. Best price I could find. They are the real deal. You will need the O2 tool kit. I rented mine from Autozone. And you'll need a torque wrench and basic tools. FSM calls for 37# of torque. Being I was using a off-set tool, I did 35# torque. Make sure you have some long or a few 3/8" ratchet extenstions. I sprayed mine with PBlaster the night before. Did them Sat morning. Connectors are a PITA, take your time with a small screw driver. Overall a good 30 minute job. Might look at your vacuum line on the SAP. Mine was shot so I replaced the 4" of line while I was there and had the O2 harness out of the way.


As for Amazon... love them. Even buying my Castrol 0w-30 Edge/Syntec from them being NOBODY locally carries it. Same for the Castrol Gear oil. Amazon rocks.