question about sensors.....

[Cue]

here's one for the techies out there... do sensors just report or do they control? maybe it depends on the sensor????

i.e. if you get a fault code. could the fault likely be caused a dodgy sensor or could a dodgy sensor have altered the EMS to trip a fault?

 

[Renaultsport]

The way I see it is that the sensor feeds to the ECU and the ECU makes the adjustment depending on the information it is given. I think the ECU is given a range of values it can work within for certain things before its a fault and turning ont he warning light.

 

[eljeffo64]

It depends on the sensor - which one were you thinking of?

 

[nickboazracing]

The sensors only feed information back to the control unit. The control unit then does the controlling, hence the name! Think of a sensor as a messenger.

The control unit will have known upper and lower limit values and will always expect to recieve a value within this given range. If it does receive a value out side of this range, it will store a fault code and if neccessary display a warning light. Depending of the sophistication of the control system the control unit will recognise, value too high, too low, out of range or simply that it is not receiving a value at all or one that it recognises.

From there, it may be a faulty sensor, or that the sensor reading correctly but the component it is reading from is faulty.

 

[Cue]

hhmmn. then it's off the garage... drove the T for the first time in a week or so and i noticed that it was running very 'lumpy' then the engine warning light was tripped. i wondered if the Lambda sensor was on the ay out but it could be there's a fuel/spark or an other issue that's tripped the sensor - my fault code reader just says there's a fault - nice n handy that :roll:

 

[anth424]

new member here, hope you dont mind me joining as iv only got a 182, but iv found this a great forum if i need advice or hav a prob with the car. iv had bother with my lamda sensor of late but only the emissions light comin on. until a few days ago there was no change in the way the car run and the light wud go off after a few days. the other day it started to run lumpy as if it was only on 3 pots and backfiring! the only fault code was for the 1st sensor as usual so that was changed and bingo! case solved. comparing new sensor with old, the old one had somethin rattlin inside, god only knows wot the mixture was like.

 

[Cue]

I'll be able to find out more this friday as it's going in to a reno specialist... will report back.

 

[blueseidboy]

Where in yorkshire are you cue? I'm in sheffield and have an rs tuner. May be able to shed some more light on the problem?

 

[Cue]

Halifax area - although it's not being driven until friday anyway so won't come to any harm. thanks for the offer though.

I wonder if it works on BMW's also lol....

 

[Cue]

it was the upstream O2 sensor which had gone.... caused slightly lumpy running.