[ontheball247]

Considering i just bought the car, and I like everything fresh, i figured i'd change the O2 sensors along with everything else on my E36 328i coupe.

But then i saw they're about £50 each from GSF, and i need (ok, so i dont need..its more like i want) 2 pre-cat sensors, n 2 post-cat sensors (4 in total).
That's about £200 for the lot.

First thing is, can u get em cheaper (I have looked, but GSF look like the cheapest so far), n second thing is, are they worth changing? Considering...

With mixed motorway and local driving im averaging about 50miles out of a tenner of Shell V-power fuel (i.e. just under 25mpg).

What I've done;
Oil n filter changed (10w-40 part synth- considering changing again, to 5w-40 fully synth, or 5w-30 fully synth).
Air filter changed.

Still to change/do;
Slick 50 fuel system cleaner;
After that tank of fuel, change the fuel filter;
Then change the spark plugs.

I mean 25mpg out of a 2.8 petrol engine aint bad, but the idea i had from wat i read b4 buyin it, was i shud average about 30-35mpg.

So considering my mpg, after doin the rest of the stuff thats still on my list, IF my mpg stays the same, would any1 recommend still changing the O2 sensors?
Or did i read wrong? is 25mpg with mixed motorway n town driving good for a 328? considering i drive fairly sensibly- If I've missed anything on my service checklist, please let me kno.

Cheers for reading, n for all responses.
Baz.

 

[RJB328i]

hello mate
before your change the lamba sensors go to you local mot staion and ask them to do an emissons test, if all ok y change, would have fault you would get 30mpg on motorway and around 23mpg upwards in town, would change spark plugs, air filter, fuel filter and have a engine pug in for a dieonostic just to see all is ok, hope this helps

 

[steve23002]

If the above shows emmissions faults. DO not get the cheap sensors, they do not have the measurement range of the O.E sensors.
Stick with a Bosch or O.E sensor....:thumbsup

 

[RJB328i]

Morning Steve
had mine does yesterday for a tenner:thumbsup, all clear

 

[steve23002]

Morning Steve
had mine does yesterday for a tenner:thumbsup, all clear

Job done.............:thumbsup

 

[ontheball247]

Aight, kool. sounds ok then. soon as im done with the spark plugs, etc, i'll get a full diagnostic..soon as i find where to get it from. im near wimbledon if any1 can recommend a garage around here.

Cheers guys.

 

[hamish262001]

there are only 2 lammbda sensors on a 328 both in the exhaust manifold
and as said above get the good ones
as far as I can find out NTK is standard fitment on the 328 not bosch i'm looking for a set for mine at the right price :confused

 

[steve23002]

Ntk are a good make. They are just the lambda sensor division of NGK...:thumbsup

You are right hamish, there is one in each exhaust manifold.....

 

[ontheball247]

that's great news then. i was under the influence that there's 2 pre-cat n 2 post-cat sensors. I guess that's just USDM then. I'll look to get fresh ones then anyway. n ntk, or bosch it is

Thanx again.

 

[steve23002]

Keep us posted how you get on....:thumbsup

 

[ontheball247]

K, had a look under the car, n i see the sensors, but where r the cables goin to? i cudnt seem to find the plugs to em.

 

[steve23002]

IIRC take off the top engine covers and the wires run next to the fuel rail. They plug in there......:thumbsup

 

[ontheball247]

Thanks, i'll try do it same tim as the spark plugs then. My O2 sensors have the BMW logo on them, so they're OE parts. Does this mean there's a good chance they aint been changed in 69k then?

 

[steve23002]

Thanks, i'll try do it same tim as the spark plugs then. My O2 sensors have the BMW logo on them, so they're OE parts. Does this mean there's a good chance they aint been changed in 69k then?

Oh yes. There is a very good chance they have not been changed. They often still work, but lose there efficiency over time.....:frown