pogeot 206 03 reg 1.4

[cjrboat]

hi every one my brother is in durahm and i an in skelmersdale so i need your expert help again he has a problem with a missfire in low gears and i sent my code reader to him by post to check for fault code and PO136 AND PO141 THE HEATED OXYGEN SENSOR BUT IT HAS 2 1 BEFORE THE KAT AND ONE AFTER THE KAT how can i check thes senders it has a black wire grey wire white wire purple wire i have a good multi meter but dont know what wire go to the heater and signal for ecu any help as i will go over to help hem on sunday the code read as bank=1 if this helps thanks bazz

 

[Mursal]

Bank 1 would be the one before the CAT.

Check the plugs on the wiring loom for bad/corroded connections?

Then just swap the sensors and see if the problem follows the sensor.

They might be tight

 

[Burnerman]

I'm wondering if there are coil pack issues here....any other codes?
If it helps, the original sensor heaters have white wires, but the replacements may be red, black or even purple. No matter, they have a one way connection where they join the loom.
As far as I recall, pre and post cat sensors have a different part number, but I don't know what the difference is.
John

 

[Belle427]

Lambdas don't usually cause misfires, as John suggested start with the basics such as plugs etc

 

[cjrboat]

thanks for your reply guys regards the coil pack and plugs both were changed by a garage and still the same why the garage didn't diagnose the fault first ?????????? that's why i sent my diagnostic unit over for him to look and it showed the 2 codes 136 and 141 both relate to the lambda sensor the reason the different part No is different is the length of the cable can anyone tell me what wires are for the heater and what wires are for the ecu input so i can check the old unit before removing it thanks for your help bazz going to Durham in the morning

 

[Belle427]

The heater circuit is normally 2 white wires but you say you only have 1?
Try comparing the pre cat and after cat for the readings, I'm not sure on the colours I'm afraid.
You should expect to see 0.1v to 0.9v switching roughly every second with the vehicle held at 2000-2500rpm across the signal wires, your multimeter may not be capable of reading it though.
just to add the after cat sensors voltage should be more constant at around 0.5v if the mixture is good and the cat is doing its job

 

[Burnerman]

Good post that, though I've never had lambda sensors causing a misfire.....poor tick over and throttle response, certainly!
I'm also steering well away from pattern exhaust parts for French cars, too.....fitted a new cat and 2 sensors to a 1.1 206, and the thing still didn't pass the bloody emissions test
John

 

[Belle427]

i think even the type approved numbered cats are rubbish but there isnt much choice.

 

[cjrboat]

went to Durham today sad weather but that's the north changed the sensor and cleared the fault codes see what happens tomorrow cheers every one for your help