my car nissan almera 2001, 1.5, mamual, engine warning light on for certain time,according to snap on code reader, fault code was p0141 heater circuit problem on bank 1 oxygen sensor 2.things i"ve done:1. managed to change no. 2 sensor, light still on, drive round blocks 10 mins, light still on2. :::: to check the voltage of no 1. sensor(by the cat), it read 356mv, try to check no.2 sensor volt, weather getting dark, and 4 wires on the plug, dont know which is which, gave up.(when checking no.1 sensor volt, eng was idling speed)3. all wires ,fues, seems ok, except ecm plug connection( could not find location)please help :1. how to repair this circuit problem2. do i have to check all the sensors one by one3. how to check ecm 4. is the mixture too lean, how to tune it up5. location of ecm unit6. if battery is disconneted,will the fault codes come back again7. by the right hand side of engine bay, there is a small rectangular rely box,one main relay missing, doest it matter8. please show me the right path to get rid this light,many many thanks!!!!!!!!!!!!!!!!!!
Country: United KingdomMake: Nissan/almeraYear: 2001Engine: 1.5 l
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This is the only code stored?
hi cardoctor 69, can u tell me what more information do u need ?
I just need to know if there were any other codes stored?
NO, ONLY ONE , THANKS,
Check the blue wire with the yellow stripe at the back of the connector of the sensor these break all the time let me know if it's broken.
THEY ARE NOT BROKEN ,THANKS
Ok has the mass air flow sensor been checked? Was there any work done prior to this happening?
hi, cardoctor69, a lot of sensors volts behave funny, especially maf, let me list them, maf-------------engine idling-----flucuating between 14.1v to 181.8 mvmaf-------------2500rpm-------------14.2vmaf-------------ignition on------------12.04vearth----------ignition on--------------7.42vevap valve-----ignition on-----------8.4mvegr-------ignition on temp 0 degree-------12.2vegr-------engine running 100 degree------14viat--------ignition on----------12.21v ,i will double check them ,thanks
Honestly I would start with the maf sensor next .
hi, cardoctor69, i put the maf sensor, light is on, what else u can think of , please tell me what to do next to solve the problem( warning light still on),before i pay,thanks,