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New 02 sensors

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Just installed 2 new 02 sensors today--the old ones had been in there for about 100k miles and when I took them out the tips were white-Is this bad and if so what could cause it--I researched and found that white tips could be from using nonsensor safe silicone gasket material. Well I thought that's all I ever have used on the car--could it be from the hoses that I am using for my oil catch can--They are fuel line hoses which I would think would be sensor safe--but heck you can't tell on everything
I replaced the Bosch with Denso 02 plugs this time--they cost a few dollars more--but from what I have read they react faster than the bosch--the but dyno says I like em--but I guess that time will tell when out on the road and the gas mileage records will prove or disprove what my feelings are about the new sensors--Ohh yeah, mileage on the car I bought new is now at 240k miles--
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I'm about to replace the post-cat O2 sensors. No codes yet but at 162K miles I rather change them now, besides I will replace the giubo (flex disc) and center support bearing.
Pre-cat O2 sensors were changed when the car had about 108K miles

Sent from my MB860 using Bimmer App
there is no sense to replace the post-cat O2 sensors unless you have a code. Pre-cat is a different story. DME does nothing with the post cat sensors for mixture, they will not effect performance/fuel economy. They are only used to monitor the cats. I would save the money for something else for now.
I'm about to replace the post-cat O2 sensors. No codes yet but at 162K miles I rather change them now, besides I will replace the giubo (flex disc) and center support bearing.
Pre-cat O2 sensors were changed when the car had about 108K miles

Sent from my MB860 using Bimmer App
when metal is white it is usually from getting very hot. how bad are you talking about? These things see temps around 1000F I wouldn't be surprised to see them a little white. I don't know about the silicon but a lean burn...could maybe get them hotter than normal.
Just installed 2 new 02 sensors today--the old ones had been in there for about 100k miles and when I took them out the tips were white-Is this bad and if so what could cause it--I researched and found that white tips could be from using nonsensor safe silicone gasket material. Well I thought that's all I ever have used on the car--could it be from the hoses that I am using for my oil catch can--They are fuel line hoses which I would think would be sensor safe--but heck you can't tell on everything
I replaced the Bosch with Denso 02 plugs this time--they cost a few dollars more--but from what I have read they react faster than the bosch--the but dyno says I like em--but I guess that time will tell when out on the road and the gas mileage records will prove or disprove what my feelings are about the new sensors--Ohh yeah, mileage on the car I bought new is now at 240k miles--
No worries, mate; mine were white, too, when I took them out.

100k for pre-cat sensors is a good time to replace them - they get lazy.
oh ok cool, i will request a rma # then :D
there is no sense to replace the post-cat O2 sensors unless you have a code. Pre-cat is a different story. DME does nothing with the post cat sensors for mixture, they will not effect performance/fuel economy. They are only used to monitor the cats. I would save the money for something else for now.
Thanks for the info on the white tips--on the Denso 02 sensors--I drove to my office this AM and worked on a couple of things , then back home--and then back to the office and back home again
It's about 10 miles or so each way--normally I get about 19 each way--today with the new sensors it was 24 average back and forth both times---haven't been out on the road yet to see whats going on, but that's next--
Where'd you get the Denso's?
Doru--Bought the Denso's at AutoZone--they were 85 bucks each--I had read around on them and from what I had gleened , they react faster than the Bosch--don't know if thats better in our case, but thought I would give them ago,,they are a few bucks more but just wanted to try a diff brand this time and had heard good things about this brand---Just returned frrom a 60 miles jaunt to and back to my Mountain get away--Tailpipe is clean as can bee--no residue when I inspected it and my gass mileage was up a few points also---the car feels lighter taking off and throttle responce is real crisp as well. Don't know how they will work in a month or two, but will be keeping an eye on what's happening and report back with findings
Good to see I'm not the only one to experience improved gas mileage with new O2 sensors. I'm getting about a 5% improvement. I also got a little smoother low end, almost like post-Vanos seals. I changed mine at 104K.
I changed the OEM O2 sensors when I hit +/- 60 k miles. They were OEM, and I had a code: "ageing O2 sensors". Forgot what the number associated the code was.
Placed the Bosch 13477 in. Have them since.
Did some extensive work on the engine in time (Vanos, DISA, cleaned TB & ICV, new injectors, new spark plugs, new vac hoses, etc). Gas mileage improved, but it started to go S again. Ever so slightly. Not sure what's going on. Tailpipe looks clean, engine starts just by showing the key, no stalls, no weird idling, just a blissful low rumble. Engine turns smoothly whether it's cold or warm. What gives?
Doru try this
Update ECU & Reset engine adaption values
Update tranny software & Reset tranny adaptation values
See foam on a long drive in tank
+5% better gas mileage guaranty
With the new sensors installed--should I reset the adaptations?
How do you do that? i have a GT1, have no idea how to do it. That piece of software works exactly like the German grammar: backwards.
Took me forever to figure out simple things like how to turn on or off certain features. And even then......
Doru try this
Update ECU & Reset engine adaption values
Update tranny software & Reset tranny adaptation values
See foam on a long drive in tank
+5% better gas mileage guaranty
^I'm interested to know too. I've just had my SSS Progman v32 installed, so I'll keep my finger crossed. According to my research, it will update ECU & Tranny software. Progman is so much more user friendly since it's a dealer coding software, unlike DIS GT1 is factory coding software.
Yes but they will reset them selves after like 20 miles of driving.
With the new sensors installed--should I reset the adaptations?
Do you have INPA? It is easy on this...

just open it up>select your body style>select engine> select your DME> click on the "error" button on bottom> click on adaptations.
What is your current satisfaction with the Denso O2 Sensors? O2 sensors are next on my list and I was curious about the Denso vs Bosch performance wise.

**Nevermind- I read your update in another post topic. Maybe a link should be dropped which forwards to it?.
Don't know how they will work in a month or two, but will be keeping an eye on what's happening and report back with findings
The Denso sensors are still working great and I give them a thumbs up--my average between highway and city mileage has gone from 23.4 to 25.8 and highway is around 31 to the gallon--
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