Air fuel ratio sensor or lambda sensor ?
 

Hi all,i have started a new thread as im a bit confused and would like some clarification if possible please.car is my 02 bugeye sti prodrive.
Im getting error code 0031 which is HO2S bank 1 sensor 1 heater circuit low.i was imformed via sn and my mapper it would be o2/lambda sensor in manifold (via plastic wheel liner behind o/s front wheel) but,when i asked for lambda/o2 sensor at main dealers she said that its not an applicable part and that its a air fuel ratio sensor ! Im confused . Com ! Also if i order it firstly its £360 :eek: and secondly it cant be returned if wrong one.(i have another place i can order it from but need the correct part number and correct sensor)

Can any one say in simple terms wheather its the one by plastic wheel liner behind o/s wheel i need and is it air fuel ratio sensor or lambda please :wonder::cuckoo:
Many thanks in advance,carl. :thumb:

the 02 sensor or lambda is what monitors the AFR`s and tells the ecu what is happening

So it is the air fuel ratio sensor (as the dealer says) that i need thats 4 wire PRE TURBO ?

For newage - Bank 1 Sensor 1 is the first sensor in the exhaust, namely the A/F sensor in the manifold, accessible via the flap in the offside wheel arch.
It's called an A/F sensor as it looks after the Air/Fuel ratio, but is in fact a wideband lambda sensor (as against an ordinary lambda used for checking O2 values after the cats).

Item 1 on this page...........

http://opposedforces.com/parts/impre...llustration_2/


and available at a reasonable price from here.............

http://www.importcarparts.co.uk/part...var=0&dc=&gen=

Others who have bought sensors off ebay have sometimes found they are not up to scratch or fail very early.

Also worth checking that the wiring hasn't become affected from heat around the up pipe and melted causing the heater circuit failure

world car parts are popular for genuine sensors at good prices also

Thankyou very much don clarke,my mapper put me on to just lambdas in hull and says they are oe ones direct from bosch instead of subaru thinking of a number and doubleing it! That first link you gave me is what subaru faxed me over today too, but then she sent another with 2nd o2sensor on and confused me when saying its afr sensor.lol but now i know.thanks again mate and to you jdm stig,
Carl.

While im waiting for part to come,gonna order tomoz,my mate has ecu explorer,what would a knackered 1st sensor show as ? Also can check rear o2 one aswell if i knew what to look for lol,:norty::norty: any clues as to what figures to look out for ?:thumb:

Its one in headers at uppipe as you first said

Cheers mate, just didnt want to mix up part numbers and get wrong one as money is tight at the mo,:thumb:

a knackered sensor will show 14.7 afr and will not change when you rev the car.

Can you also get lean periods that sporadically appear, like a hesitation? Mine drops to 17-18:1 at low revs sometimes, just for a half second or so. The car stutters when that happens.

£130 bucks from eurocarparts ps its actually a denso sensor not Bosch

Not sure but bosch may make them,could be wrong tho.

it's a4 wire denso sensor trust me :thumb:

not 100% sure, likely the car is running open loop because the 02 is faulty so the ecu is running off the fuel map "circa", the car needs to be plugged in really to see what the ecu is trying to do to compensate for the fault.

Hesitation can be a number of things. :cry:

Well my a/f oxygen lamda sensor has gone, so after some investigation and pricein heres wot i found:

1, subaru want £342....(thats just for the part)..world car parts 01526 348504 wanted £94 delivered.


2. the part is denso 22641 aa042 (2349011) both companys supply exactly the same part, by the same company with the same number on it.....

i replaced the part last year & have had no problems at all with it..

hope this helps..
shaun...